version 1.16, 1995/06/03 14:24:42
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version 1.24, 1995/11/15 17:29:07
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@comment The source is gforth.ds, from which gforth.texi is generated |
@comment The source is gforth.ds, from which gforth.texi is generated |
@comment %**start of header (This is for running Texinfo on a region.) |
@comment %**start of header (This is for running Texinfo on a region.) |
@setfilename gforth.info |
@setfilename gforth.info |
@settitle GNU Forth Manual |
@settitle Gforth Manual |
@comment @setchapternewpage odd |
@comment @setchapternewpage odd |
@comment %**end of header (This is for running Texinfo on a region.) |
@comment %**end of header (This is for running Texinfo on a region.) |
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@ifinfo |
@ifinfo |
This file documents GNU Forth 0.0 |
This file documents Gforth 0.1 |
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Copyright @copyright{} 1994 GNU Forth Development Group |
Copyright @copyright{} 1995 Free Software Foundation, Inc. |
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Permission is granted to make and distribute verbatim copies of |
Permission is granted to make and distribute verbatim copies of |
this manual provided the copyright notice and this permission notice |
this manual provided the copyright notice and this permission notice |
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Line 36 Copyright @copyright{} 1994 GNU Forth De
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of in the original English. |
of in the original English. |
@end ifinfo |
@end ifinfo |
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@finalout |
@titlepage |
@titlepage |
@sp 10 |
@sp 10 |
@center @titlefont{GNU Forth Manual} |
@center @titlefont{Gforth Manual} |
@sp 2 |
@sp 2 |
@center for version 0.0 |
@center for version 0.1 |
@sp 2 |
@sp 2 |
@center Anton Ertl |
@center Anton Ertl |
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@sp 3 |
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@center This manual is under construction |
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@comment The following two commands start the copyright page. |
@comment The following two commands start the copyright page. |
@page |
@page |
@vskip 0pt plus 1filll |
@vskip 0pt plus 1filll |
Copyright @copyright{} 1994 GNU Forth Development Group |
Copyright @copyright{} 1995 Free Software Foundation, Inc. |
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@comment !! Published by ... or You can get a copy of this manual ... |
@comment !! Published by ... or You can get a copy of this manual ... |
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Line 72 Copyright @copyright{} 1994 GNU Forth De
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Line 75 Copyright @copyright{} 1994 GNU Forth De
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@node Top, License, (dir), (dir) |
@node Top, License, (dir), (dir) |
@ifinfo |
@ifinfo |
GNU Forth is a free implementation of ANS Forth available on many |
Gforth is a free implementation of ANS Forth available on many |
personal machines. This manual corresponds to version 0.0. |
personal machines. This manual corresponds to version 0.1. |
@end ifinfo |
@end ifinfo |
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|
@menu |
@menu |
* License:: |
* License:: |
* Goals:: About the GNU Forth Project |
* Goals:: About the Gforth Project |
* Other Books:: Things you might want to read |
* Other Books:: Things you might want to read |
* Invocation:: Starting GNU Forth |
* Invocation:: Starting Gforth |
* Words:: Forth words available in GNU Forth |
* Words:: Forth words available in Gforth |
* ANS conformance:: Implementation-defined options etc. |
* ANS conformance:: Implementation-defined options etc. |
* Model:: The abstract machine of GNU Forth |
* Model:: The abstract machine of Gforth |
* Emacs and GForth:: The GForth Mode |
* Emacs and Gforth:: The Gforth Mode |
* Internals:: Implementation details |
* Internals:: Implementation details |
* Bugs:: How to report them |
* Bugs:: How to report them |
* Pedigree:: Ancestors of GNU Forth |
* Pedigree:: Ancestors of Gforth |
* Word Index:: An item for each Forth word |
* Word Index:: An item for each Forth word |
* Node Index:: An item for each node |
* Node Index:: An item for each node |
@end menu |
@end menu |
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|
@node License, Goals, Top, Top |
@node License, Goals, Top, Top |
@unnumbered License |
@unnumbered GNU GENERAL PUBLIC LICENSE |
!! Insert GPL here |
@center Version 2, June 1991 |
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@display |
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Copyright @copyright{} 1989, 1991 Free Software Foundation, Inc. |
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675 Mass Ave, Cambridge, MA 02139, USA |
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Everyone is permitted to copy and distribute verbatim copies |
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of this license document, but changing it is not allowed. |
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@end display |
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@unnumberedsec Preamble |
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The licenses for most software are designed to take away your |
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freedom to share and change it. By contrast, the GNU General Public |
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License is intended to guarantee your freedom to share and change free |
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software---to make sure the software is free for all its users. This |
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General Public License applies to most of the Free Software |
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Foundation's software and to any other program whose authors commit to |
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using it. (Some other Free Software Foundation software is covered by |
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the GNU Library General Public License instead.) You can apply it to |
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your programs, too. |
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When we speak of free software, we are referring to freedom, not |
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price. Our General Public Licenses are designed to make sure that you |
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have the freedom to distribute copies of free software (and charge for |
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this service if you wish), that you receive source code or can get it |
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if you want it, that you can change the software or use pieces of it |
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in new free programs; and that you know you can do these things. |
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To protect your rights, we need to make restrictions that forbid |
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anyone to deny you these rights or to ask you to surrender the rights. |
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These restrictions translate to certain responsibilities for you if you |
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distribute copies of the software, or if you modify it. |
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For example, if you distribute copies of such a program, whether |
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gratis or for a fee, you must give the recipients all the rights that |
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you have. You must make sure that they, too, receive or can get the |
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source code. And you must show them these terms so they know their |
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rights. |
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We protect your rights with two steps: (1) copyright the software, and |
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(2) offer you this license which gives you legal permission to copy, |
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distribute and/or modify the software. |
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Also, for each author's protection and ours, we want to make certain |
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that everyone understands that there is no warranty for this free |
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software. If the software is modified by someone else and passed on, we |
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want its recipients to know that what they have is not the original, so |
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that any problems introduced by others will not reflect on the original |
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authors' reputations. |
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Finally, any free program is threatened constantly by software |
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patents. We wish to avoid the danger that redistributors of a free |
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program will individually obtain patent licenses, in effect making the |
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program proprietary. To prevent this, we have made it clear that any |
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patent must be licensed for everyone's free use or not licensed at all. |
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The precise terms and conditions for copying, distribution and |
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modification follow. |
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@iftex |
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@unnumberedsec TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION |
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@end iftex |
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@ifinfo |
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@center TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION |
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@end ifinfo |
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@enumerate 0 |
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@item |
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This License applies to any program or other work which contains |
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a notice placed by the copyright holder saying it may be distributed |
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under the terms of this General Public License. The ``Program'', below, |
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refers to any such program or work, and a ``work based on the Program'' |
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means either the Program or any derivative work under copyright law: |
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that is to say, a work containing the Program or a portion of it, |
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either verbatim or with modifications and/or translated into another |
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language. (Hereinafter, translation is included without limitation in |
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the term ``modification''.) Each licensee is addressed as ``you''. |
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Activities other than copying, distribution and modification are not |
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covered by this License; they are outside its scope. The act of |
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running the Program is not restricted, and the output from the Program |
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is covered only if its contents constitute a work based on the |
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Program (independent of having been made by running the Program). |
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Whether that is true depends on what the Program does. |
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@item |
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You may copy and distribute verbatim copies of the Program's |
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source code as you receive it, in any medium, provided that you |
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conspicuously and appropriately publish on each copy an appropriate |
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copyright notice and disclaimer of warranty; keep intact all the |
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notices that refer to this License and to the absence of any warranty; |
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and give any other recipients of the Program a copy of this License |
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along with the Program. |
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You may charge a fee for the physical act of transferring a copy, and |
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you may at your option offer warranty protection in exchange for a fee. |
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@item |
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You may modify your copy or copies of the Program or any portion |
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of it, thus forming a work based on the Program, and copy and |
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distribute such modifications or work under the terms of Section 1 |
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above, provided that you also meet all of these conditions: |
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@enumerate a |
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@item |
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You must cause the modified files to carry prominent notices |
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stating that you changed the files and the date of any change. |
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@item |
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You must cause any work that you distribute or publish, that in |
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whole or in part contains or is derived from the Program or any |
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part thereof, to be licensed as a whole at no charge to all third |
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parties under the terms of this License. |
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@item |
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If the modified program normally reads commands interactively |
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when run, you must cause it, when started running for such |
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interactive use in the most ordinary way, to print or display an |
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announcement including an appropriate copyright notice and a |
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notice that there is no warranty (or else, saying that you provide |
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a warranty) and that users may redistribute the program under |
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these conditions, and telling the user how to view a copy of this |
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License. (Exception: if the Program itself is interactive but |
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does not normally print such an announcement, your work based on |
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the Program is not required to print an announcement.) |
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@end enumerate |
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These requirements apply to the modified work as a whole. If |
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identifiable sections of that work are not derived from the Program, |
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and can be reasonably considered independent and separate works in |
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themselves, then this License, and its terms, do not apply to those |
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sections when you distribute them as separate works. But when you |
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distribute the same sections as part of a whole which is a work based |
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on the Program, the distribution of the whole must be on the terms of |
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this License, whose permissions for other licensees extend to the |
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entire whole, and thus to each and every part regardless of who wrote it. |
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Thus, it is not the intent of this section to claim rights or contest |
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your rights to work written entirely by you; rather, the intent is to |
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exercise the right to control the distribution of derivative or |
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collective works based on the Program. |
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In addition, mere aggregation of another work not based on the Program |
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with the Program (or with a work based on the Program) on a volume of |
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a storage or distribution medium does not bring the other work under |
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the scope of this License. |
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@item |
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You may copy and distribute the Program (or a work based on it, |
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under Section 2) in object code or executable form under the terms of |
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Sections 1 and 2 above provided that you also do one of the following: |
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@enumerate a |
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@item |
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Accompany it with the complete corresponding machine-readable |
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source code, which must be distributed under the terms of Sections |
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1 and 2 above on a medium customarily used for software interchange; or, |
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@item |
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Accompany it with a written offer, valid for at least three |
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years, to give any third party, for a charge no more than your |
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cost of physically performing source distribution, a complete |
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machine-readable copy of the corresponding source code, to be |
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distributed under the terms of Sections 1 and 2 above on a medium |
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customarily used for software interchange; or, |
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@item |
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Accompany it with the information you received as to the offer |
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to distribute corresponding source code. (This alternative is |
|
allowed only for noncommercial distribution and only if you |
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received the program in object code or executable form with such |
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an offer, in accord with Subsection b above.) |
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@end enumerate |
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The source code for a work means the preferred form of the work for |
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making modifications to it. For an executable work, complete source |
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code means all the source code for all modules it contains, plus any |
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associated interface definition files, plus the scripts used to |
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control compilation and installation of the executable. However, as a |
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special exception, the source code distributed need not include |
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anything that is normally distributed (in either source or binary |
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form) with the major components (compiler, kernel, and so on) of the |
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operating system on which the executable runs, unless that component |
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itself accompanies the executable. |
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If distribution of executable or object code is made by offering |
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access to copy from a designated place, then offering equivalent |
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access to copy the source code from the same place counts as |
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distribution of the source code, even though third parties are not |
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compelled to copy the source along with the object code. |
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@item |
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You may not copy, modify, sublicense, or distribute the Program |
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except as expressly provided under this License. Any attempt |
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otherwise to copy, modify, sublicense or distribute the Program is |
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void, and will automatically terminate your rights under this License. |
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However, parties who have received copies, or rights, from you under |
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this License will not have their licenses terminated so long as such |
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parties remain in full compliance. |
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@item |
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You are not required to accept this License, since you have not |
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signed it. However, nothing else grants you permission to modify or |
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distribute the Program or its derivative works. These actions are |
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prohibited by law if you do not accept this License. Therefore, by |
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modifying or distributing the Program (or any work based on the |
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Program), you indicate your acceptance of this License to do so, and |
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all its terms and conditions for copying, distributing or modifying |
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the Program or works based on it. |
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@item |
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Each time you redistribute the Program (or any work based on the |
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Program), the recipient automatically receives a license from the |
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original licensor to copy, distribute or modify the Program subject to |
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these terms and conditions. You may not impose any further |
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restrictions on the recipients' exercise of the rights granted herein. |
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You are not responsible for enforcing compliance by third parties to |
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this License. |
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@item |
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If, as a consequence of a court judgment or allegation of patent |
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infringement or for any other reason (not limited to patent issues), |
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conditions are imposed on you (whether by court order, agreement or |
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otherwise) that contradict the conditions of this License, they do not |
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excuse you from the conditions of this License. If you cannot |
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distribute so as to satisfy simultaneously your obligations under this |
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License and any other pertinent obligations, then as a consequence you |
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may not distribute the Program at all. For example, if a patent |
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license would not permit royalty-free redistribution of the Program by |
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all those who receive copies directly or indirectly through you, then |
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the only way you could satisfy both it and this License would be to |
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refrain entirely from distribution of the Program. |
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If any portion of this section is held invalid or unenforceable under |
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any particular circumstance, the balance of the section is intended to |
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apply and the section as a whole is intended to apply in other |
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circumstances. |
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It is not the purpose of this section to induce you to infringe any |
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patents or other property right claims or to contest validity of any |
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such claims; this section has the sole purpose of protecting the |
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integrity of the free software distribution system, which is |
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implemented by public license practices. Many people have made |
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generous contributions to the wide range of software distributed |
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through that system in reliance on consistent application of that |
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system; it is up to the author/donor to decide if he or she is willing |
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to distribute software through any other system and a licensee cannot |
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impose that choice. |
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|
This section is intended to make thoroughly clear what is believed to |
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be a consequence of the rest of this License. |
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|
@item |
|
If the distribution and/or use of the Program is restricted in |
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certain countries either by patents or by copyrighted interfaces, the |
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original copyright holder who places the Program under this License |
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may add an explicit geographical distribution limitation excluding |
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those countries, so that distribution is permitted only in or among |
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countries not thus excluded. In such case, this License incorporates |
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the limitation as if written in the body of this License. |
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@item |
|
The Free Software Foundation may publish revised and/or new versions |
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of the General Public License from time to time. Such new versions will |
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be similar in spirit to the present version, but may differ in detail to |
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address new problems or concerns. |
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Each version is given a distinguishing version number. If the Program |
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specifies a version number of this License which applies to it and ``any |
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later version'', you have the option of following the terms and conditions |
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either of that version or of any later version published by the Free |
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Software Foundation. If the Program does not specify a version number of |
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this License, you may choose any version ever published by the Free Software |
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Foundation. |
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|
@item |
|
If you wish to incorporate parts of the Program into other free |
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programs whose distribution conditions are different, write to the author |
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to ask for permission. For software which is copyrighted by the Free |
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Software Foundation, write to the Free Software Foundation; we sometimes |
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make exceptions for this. Our decision will be guided by the two goals |
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of preserving the free status of all derivatives of our free software and |
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of promoting the sharing and reuse of software generally. |
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|
@iftex |
@iftex |
|
@heading NO WARRANTY |
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@end iftex |
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@ifinfo |
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@center NO WARRANTY |
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@end ifinfo |
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|
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@item |
|
BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY |
|
FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN |
|
OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES |
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PROVIDE THE PROGRAM ``AS IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED |
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OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
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MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS |
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TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE |
|
PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, |
|
REPAIR OR CORRECTION. |
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@item |
|
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING |
|
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR |
|
REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, |
|
INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING |
|
OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED |
|
TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY |
|
YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER |
|
PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE |
|
POSSIBILITY OF SUCH DAMAGES. |
|
@end enumerate |
|
|
|
@iftex |
|
@heading END OF TERMS AND CONDITIONS |
|
@end iftex |
|
@ifinfo |
|
@center END OF TERMS AND CONDITIONS |
|
@end ifinfo |
|
|
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@page |
|
@unnumberedsec How to Apply These Terms to Your New Programs |
|
|
|
If you develop a new program, and you want it to be of the greatest |
|
possible use to the public, the best way to achieve this is to make it |
|
free software which everyone can redistribute and change under these terms. |
|
|
|
To do so, attach the following notices to the program. It is safest |
|
to attach them to the start of each source file to most effectively |
|
convey the exclusion of warranty; and each file should have at least |
|
the ``copyright'' line and a pointer to where the full notice is found. |
|
|
|
@smallexample |
|
@var{one line to give the program's name and a brief idea of what it does.} |
|
Copyright (C) 19@var{yy} @var{name of author} |
|
|
|
This program is free software; you can redistribute it and/or modify |
|
it under the terms of the GNU General Public License as published by |
|
the Free Software Foundation; either version 2 of the License, or |
|
(at your option) any later version. |
|
|
|
This program is distributed in the hope that it will be useful, |
|
but WITHOUT ANY WARRANTY; without even the implied warranty of |
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
|
GNU General Public License for more details. |
|
|
|
You should have received a copy of the GNU General Public License |
|
along with this program; if not, write to the Free Software |
|
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
|
@end smallexample |
|
|
|
Also add information on how to contact you by electronic and paper mail. |
|
|
|
If the program is interactive, make it output a short notice like this |
|
when it starts in an interactive mode: |
|
|
|
@smallexample |
|
Gnomovision version 69, Copyright (C) 19@var{yy} @var{name of author} |
|
Gnomovision comes with ABSOLUTELY NO WARRANTY; for details |
|
type `show w'. |
|
This is free software, and you are welcome to redistribute it |
|
under certain conditions; type `show c' for details. |
|
@end smallexample |
|
|
|
The hypothetical commands @samp{show w} and @samp{show c} should show |
|
the appropriate parts of the General Public License. Of course, the |
|
commands you use may be called something other than @samp{show w} and |
|
@samp{show c}; they could even be mouse-clicks or menu items---whatever |
|
suits your program. |
|
|
|
You should also get your employer (if you work as a programmer) or your |
|
school, if any, to sign a ``copyright disclaimer'' for the program, if |
|
necessary. Here is a sample; alter the names: |
|
|
|
@smallexample |
|
Yoyodyne, Inc., hereby disclaims all copyright interest in the program |
|
`Gnomovision' (which makes passes at compilers) written by James Hacker. |
|
|
|
@var{signature of Ty Coon}, 1 April 1989 |
|
Ty Coon, President of Vice |
|
@end smallexample |
|
|
|
This General Public License does not permit incorporating your program into |
|
proprietary programs. If your program is a subroutine library, you may |
|
consider it more useful to permit linking proprietary applications with the |
|
library. If this is what you want to do, use the GNU Library General |
|
Public License instead of this License. |
|
|
|
@iftex |
|
@node Preface |
|
@comment node-name, next, previous, up |
@unnumbered Preface |
@unnumbered Preface |
This manual documents GNU Forth. The reader is expected to know |
@cindex Preface |
|
This manual documents Gforth. The reader is expected to know |
Forth. This manual is primarily a reference manual. @xref{Other Books} |
Forth. This manual is primarily a reference manual. @xref{Other Books} |
for introductory material. |
for introductory material. |
@end iftex |
@end iftex |
|
|
@node Goals, Other Books, License, Top |
@node Goals, Other Books, License, Top |
@comment node-name, next, previous, up |
@comment node-name, next, previous, up |
@chapter Goals of GNU Forth |
@chapter Goals of Gforth |
@cindex Goals |
@cindex Goals |
The goal of the GNU Forth Project is to develop a standard model for |
The goal of the Gforth Project is to develop a standard model for |
ANSI Forth. This can be split into several subgoals: |
ANSI Forth. This can be split into several subgoals: |
|
|
@itemize @bullet |
@itemize @bullet |
@item |
@item |
GNU Forth should conform to the ANSI Forth standard. |
Gforth should conform to the ANSI Forth standard. |
@item |
@item |
It should be a model, i.e. it should define all the |
It should be a model, i.e. it should define all the |
implementation-dependent things. |
implementation-dependent things. |
Line 121 It should become standard, i.e. widely a
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Line 515 It should become standard, i.e. widely a
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is the most difficult one. |
is the most difficult one. |
@end itemize |
@end itemize |
|
|
To achieve these goals GNU Forth should be |
To achieve these goals Gforth should be |
@itemize @bullet |
@itemize @bullet |
@item |
@item |
Similar to previous models (fig-Forth, F83) |
Similar to previous models (fig-Forth, F83) |
Line 137 Free.
|
Line 531 Free.
|
Available on many machines/easy to port. |
Available on many machines/easy to port. |
@end itemize |
@end itemize |
|
|
Have we achieved these goals? GNU Forth conforms to the ANS Forth |
Have we achieved these goals? Gforth conforms to the ANS Forth |
standard; it may be considered a model, but we have not yet documented |
standard. It may be considered a model, but we have not yet documented |
which parts of the model are stable and which parts we are likely to |
which parts of the model are stable and which parts we are likely to |
change; it certainly has not yet become a de facto standard. It has some |
change. It certainly has not yet become a de facto standard. It has some |
similarities and some differences to previous models; It has some |
similarities and some differences to previous models. It has some |
powerful features, but not yet everything that we envisioned; on RISCs |
powerful features, but not yet everything that we envisioned. We |
it is as fast as interpreters programmed in assembly, on |
certainly have achieved our execution speed goals (@pxref{Performance}). |
register-starved machines it is not so fast, but still faster than any |
It is free and available on many machines. |
other C-based interpretive implementation; it is free and available on |
|
many machines. |
|
|
|
@node Other Books, Invocation, Goals, Top |
@node Other Books, Invocation, Goals, Top |
@chapter Other books on ANS Forth |
@chapter Other books on ANS Forth |
|
|
As the standard is relatively new, there are not many books out yet. It |
As the standard is relatively new, there are not many books out yet. It |
is not recommended to learn Forth by using GNU Forth and a book that is |
is not recommended to learn Forth by using Gforth and a book that is |
not written for ANS Forth, as you will not know your mistakes from the |
not written for ANS Forth, as you will not know your mistakes from the |
deviations of the book. |
deviations of the book. |
|
|
There is, of course, the standard, the definite reference if you want to |
There is, of course, the standard, the definite reference if you want to |
write ANS Forth programs. It will be available in printed form from |
write ANS Forth programs. It is available in printed form from the |
Global Engineering Documents !! somtime in spring or summer 1994. If you |
National Standards Institute Sales Department (Tel.: USA (212) 642-4900; |
are lucky, you can still get dpANS6 (the draft that was approved as |
Fax.: USA (212) 302-1286) as document @cite{X3.215-1994} for about $200. You |
standard) by aftp from ftp.uu.net:/vendor/minerva/x3j14. |
can also get it from Global Engineering Documents (Tel.: USA (800) |
|
854-7179; Fax.: (303) 843-9880) for about $300. |
|
|
|
@cite{dpANS6}, the last draft of the standard, which was then submitted to ANSI |
|
for publication is available electronically and for free in some MS Word |
|
format, and it has been converted to HTML. Some pointers to these |
|
versions can be found through |
|
@*@file{http://www.complang.tuwien.ac.at/projects/forth.html}. |
|
|
@cite{Forth: The new model} by Jack Woehr (!! Publisher) is an |
@cite{Forth: The new model} by Jack Woehr (Prentice-Hall, 1993) is an |
introductory book based on a draft version of the standard. It does not |
introductory book based on a draft version of the standard. It does not |
cover the whole standard. It also contains interesting background |
cover the whole standard. It also contains interesting background |
information (Jack Woehr was in the ANS Forth Technical Committe). It is |
information (Jack Woehr was in the ANS Forth Technical Committe). It is |
Line 173 other languages should find it ok.
|
Line 572 other languages should find it ok.
|
@chapter Invocation |
@chapter Invocation |
|
|
You will usually just say @code{gforth}. In many other cases the default |
You will usually just say @code{gforth}. In many other cases the default |
GNU Forth image will be invoked like this: |
Gforth image will be invoked like this: |
|
|
@example |
@example |
gforth [files] [-e forth-code] |
gforth [files] [-e forth-code] |
Line 193 line. They are:
|
Line 592 line. They are:
|
|
|
@table @code |
@table @code |
@item --image-file @var{file} |
@item --image-file @var{file} |
|
@item -i @var{file} |
Loads the Forth image @var{file} instead of the default |
Loads the Forth image @var{file} instead of the default |
@file{gforth.fi}. |
@file{gforth.fi}. |
|
|
@item --path @var{path} |
@item --path @var{path} |
|
@item -p @var{path} |
Uses @var{path} for searching the image file and Forth source code |
Uses @var{path} for searching the image file and Forth source code |
files instead of the default in the environment variable |
files instead of the default in the environment variable |
@code{GFORTHPATH} or the path specified at installation time (typically |
@code{GFORTHPATH} or the path specified at installation time (typically |
Line 245 Forth words, you have to quote them or u
|
Line 646 Forth words, you have to quote them or u
|
after processing the command line (instead of entering interactive mode) |
after processing the command line (instead of entering interactive mode) |
append @code{-e bye} to the command line. |
append @code{-e bye} to the command line. |
|
|
|
If you have several versions of Gforth installed, @code{gforth} will |
|
invoke the version that was installed last. @code{gforth-@var{version}} |
|
invokes a specific version. You may want to use the option |
|
@code{--path}, if your environment contains the variable |
|
@code{GFORTHPATH}. |
|
|
Not yet implemented: |
Not yet implemented: |
On startup the system first executes the system initialization file |
On startup the system first executes the system initialization file |
(unless the option @code{--no-init-file} is given; note that the system |
(unless the option @code{--no-init-file} is given; note that the system |
Line 269 then in @file{~}, then in the normal pat
|
Line 676 then in @file{~}, then in the normal pat
|
* Blocks:: |
* Blocks:: |
* Other I/O:: |
* Other I/O:: |
* Programming Tools:: |
* Programming Tools:: |
|
* Assembler and Code words:: |
* Threading Words:: |
* Threading Words:: |
@end menu |
@end menu |
|
|
Line 285 that has become a de-facto standard for
|
Line 693 that has become a de-facto standard for
|
|
|
@table @var |
@table @var |
@item word |
@item word |
The name of the word. BTW, GNU Forth is case insensitive, so you can |
The name of the word. BTW, Gforth is case insensitive, so you can |
type the words in in lower case (However, @pxref{core-idef}). |
type the words in in lower case (However, @pxref{core-idef}). |
|
|
@item Stack effect |
@item Stack effect |
Line 293 The stack effect is written in the notat
|
Line 701 The stack effect is written in the notat
|
@var{after}}, where @var{before} and @var{after} describe the top of |
@var{after}}, where @var{before} and @var{after} describe the top of |
stack entries before and after the execution of the word. The rest of |
stack entries before and after the execution of the word. The rest of |
the stack is not touched by the word. The top of stack is rightmost, |
the stack is not touched by the word. The top of stack is rightmost, |
i.e., a stack sequence is written as it is typed in. Note that GNU Forth |
i.e., a stack sequence is written as it is typed in. Note that Gforth |
uses a separate floating point stack, but a unified stack |
uses a separate floating point stack, but a unified stack |
notation. Also, return stack effects are not shown in @var{stack |
notation. Also, return stack effects are not shown in @var{stack |
effect}, but in @var{Description}. The name of a stack item describes |
effect}, but in @var{Description}. The name of a stack item describes |
the type and/or the function of the item. See below for a discussion of |
the type and/or the function of the item. See below for a discussion of |
the types. |
the types. |
|
|
|
All words have two stack effects: A compile-time stack effect and a |
|
run-time stack effect. The compile-time stack-effect of most words is |
|
@var{ -- }. If the compile-time stack-effect of a word deviates from |
|
this standard behaviour, or the word does other unusual things at |
|
compile time, both stack effects are shown; otherwise only the run-time |
|
stack effect is shown. |
|
|
@item pronunciation |
@item pronunciation |
How the word is pronounced |
How the word is pronounced |
|
|
Line 309 system need not support all of them. So,
|
Line 724 system need not support all of them. So,
|
uses the more portable it will be in theory. However, we suspect that |
uses the more portable it will be in theory. However, we suspect that |
most ANS Forth systems on personal machines will feature all |
most ANS Forth systems on personal machines will feature all |
wordsets. Words that are not defined in the ANS standard have |
wordsets. Words that are not defined in the ANS standard have |
@code{gforth} as wordset. |
@code{gforth} or @code{gforth-internal} as wordset. @code{gforth} |
|
describes words that will work in future releases of Gforth; |
|
@code{gforth-internal} words are more volatile. Environmental query |
|
strings are also displayed like words; you can recognize them by the |
|
@code{environment} in the wordset field. |
|
|
@item Description |
@item Description |
A description of the behaviour of the word. |
A description of the behaviour of the word. |
Line 438 number will be interpreted as integer, u
|
Line 857 number will be interpreted as integer, u
|
(both @code{+} and @code{-} are allowed as signs). |
(both @code{+} and @code{-} are allowed as signs). |
|
|
Angles in floating point operations are given in radians (a full circle |
Angles in floating point operations are given in radians (a full circle |
has 2 pi radians). Note, that gforth has a separate floating point |
has 2 pi radians). Note, that Gforth has a separate floating point |
stack, but we use the unified notation. |
stack, but we use the unified notation. |
|
|
Floating point numbers have a number of unpleasant surprises for the |
Floating point numbers have a number of unpleasant surprises for the |
Line 486 doc-fatanh
|
Line 905 doc-fatanh
|
@node Stack Manipulation, Memory access, Arithmetic, Words |
@node Stack Manipulation, Memory access, Arithmetic, Words |
@section Stack Manipulation |
@section Stack Manipulation |
|
|
gforth has a data stack (aka parameter stack) for characters, cells, |
Gforth has a data stack (aka parameter stack) for characters, cells, |
addresses, and double cells, a floating point stack for floating point |
addresses, and double cells, a floating point stack for floating point |
numbers, a return stack for storing the return addresses of colon |
numbers, a return stack for storing the return addresses of colon |
definitions and other data, and a locals stack for storing local |
definitions and other data, and a locals stack for storing local |
Line 612 must only occur at specific addresses; e
|
Line 1031 must only occur at specific addresses; e
|
accessed at addresses divisible by 4. Even if a machine allows unaligned |
accessed at addresses divisible by 4. Even if a machine allows unaligned |
accesses, it can usually perform aligned accesses faster. |
accesses, it can usually perform aligned accesses faster. |
|
|
For the performance-concious: alignment operations are usually only |
For the performance-conscious: alignment operations are usually only |
necessary during the definition of a data structure, not during the |
necessary during the definition of a data structure, not during the |
(more frequent) accesses to it. |
(more frequent) accesses to it. |
|
|
Line 622 char-aligned have no use in the standard
|
Line 1041 char-aligned have no use in the standard
|
created. |
created. |
|
|
The standard guarantees that addresses returned by @code{CREATE}d words |
The standard guarantees that addresses returned by @code{CREATE}d words |
are cell-aligned; in addition, gforth guarantees that these addresses |
are cell-aligned; in addition, Gforth guarantees that these addresses |
are aligned for all purposes. |
are aligned for all purposes. |
|
|
Note that the standard defines a word @code{char}, which has nothing to |
Note that the standard defines a word @code{char}, which has nothing to |
Line 808 There are several variations on the coun
|
Line 1227 There are several variations on the coun
|
|
|
@code{LEAVE} leaves the innermost counted loop immediately. |
@code{LEAVE} leaves the innermost counted loop immediately. |
|
|
|
If @var{start} is greater than @var{limit}, a @code{?DO} loop is entered |
|
(and @code{LOOP} iterates until they become equal by wrap-around |
|
arithmetic). This behaviour is usually not what you want. Therefore, |
|
Gforth offers @code{+DO} and @code{U+DO} (as replacements for |
|
@code{?DO}), which do not enter the loop if @var{start} is greater than |
|
@var{limit}; @code{+DO} is for signed loop parameters, @code{U+DO} for |
|
unsigned loop parameters. These words can be implemented easily on |
|
standard systems, so using them does not make your programs hard to |
|
port; e.g.: |
|
@example |
|
: +DO ( compile-time: -- do-sys; run-time: n1 n2 -- ) |
|
POSTPONE over POSTPONE min POSTPONE ?DO ; immediate |
|
@end example |
|
|
@code{LOOP} can be replaced with @code{@var{n} +LOOP}; this updates the |
@code{LOOP} can be replaced with @code{@var{n} +LOOP}; this updates the |
index by @var{n} instead of by 1. The loop is terminated when the border |
index by @var{n} instead of by 1. The loop is terminated when the border |
between @var{limit-1} and @var{limit} is crossed. E.g.: |
between @var{limit-1} and @var{limit} is crossed. E.g.: |
|
|
@code{4 0 ?DO i . 2 +LOOP} prints @code{0 2} |
@code{4 0 +DO i . 2 +LOOP} prints @code{0 2} |
|
|
@code{4 1 ?DO i . 2 +LOOP} prints @code{1 3} |
@code{4 1 +DO i . 2 +LOOP} prints @code{1 3} |
|
|
The behaviour of @code{@var{n} +LOOP} is peculiar when @var{n} is negative: |
The behaviour of @code{@var{n} +LOOP} is peculiar when @var{n} is negative: |
|
|
Line 822 The behaviour of @code{@var{n} +LOOP} is
|
Line 1255 The behaviour of @code{@var{n} +LOOP} is
|
|
|
@code{ 0 0 ?DO i . -1 +LOOP} prints nothing |
@code{ 0 0 ?DO i . -1 +LOOP} prints nothing |
|
|
Therefore we recommend avoiding using @code{@var{n} +LOOP} with negative |
Therefore we recommend avoiding @code{@var{n} +LOOP} with negative |
@var{n}. One alternative is @code{@var{n} S+LOOP}, where the negative |
@var{n}. One alternative is @code{@var{u} -LOOP}, which reduces the |
case behaves symmetrical to the positive case: |
index by @var{u} each iteration. The loop is terminated when the border |
|
between @var{limit+1} and @var{limit} is crossed. Gforth also provides |
|
@code{-DO} and @code{U-DO} for down-counting loops. E.g.: |
|
|
@code{-2 0 ?DO i . -1 S+LOOP} prints @code{0 -1} |
@code{-2 0 -DO i . 1 -LOOP} prints @code{0 -1} |
|
|
@code{-1 0 ?DO i . -1 S+LOOP} prints @code{0} |
@code{-1 0 -DO i . 1 -LOOP} prints @code{0} |
|
|
@code{ 0 0 ?DO i . -1 S+LOOP} prints nothing |
@code{ 0 0 -DO i . 1 -LOOP} prints nothing |
|
|
The loop is terminated when the border between @var{limit@minus{}sgn(n)} and |
Another alternative is @code{@var{n} S+LOOP}, where the negative |
@var{limit} is crossed. However, @code{S+LOOP} is not part of the ANS |
case behaves symmetrical to the positive case: |
Forth standard. |
|
|
@code{-2 0 -DO i . -1 S+LOOP} prints @code{0 -1} |
|
|
@code{?DO} can be replaced by @code{DO}. @code{DO} enters the loop even |
The loop is terminated when the border between @var{limit@minus{}sgn(n)} |
when the start and the limit value are equal. We do not recommend using |
and @var{limit} is crossed. Unfortunately, neither @code{-LOOP} nor |
@code{DO}. It will just give you maintenance troubles. |
@code{S+LOOP} are part of the ANS Forth standard, and they are not easy |
|
to implement using standard words. If you want to write standard |
|
programs, just avoid counting down. |
|
|
|
@code{?DO} can also be replaced by @code{DO}. @code{DO} always enters |
|
the loop, independent of the loop parameters. Do not use @code{DO}, even |
|
if you know that the loop is entered in any case. Such knowledge tends |
|
to become invalid during maintenance of a program, and then the |
|
@code{DO} will make trouble. |
|
|
@code{UNLOOP} is used to prepare for an abnormal loop exit, e.g., via |
@code{UNLOOP} is used to prepare for an abnormal loop exit, e.g., via |
@code{EXIT}. @code{UNLOOP} removes the loop control parameters from the |
@code{EXIT}. @code{UNLOOP} removes the loop control parameters from the |
Line 852 FOR
|
Line 1296 FOR
|
NEXT |
NEXT |
@end example |
@end example |
This is the preferred loop of native code compiler writers who are too |
This is the preferred loop of native code compiler writers who are too |
lazy to optimize @code{?DO} loops properly. In GNU Forth, this loop |
lazy to optimize @code{?DO} loops properly. In Gforth, this loop |
iterates @var{n+1} times; @code{i} produces values starting with @var{n} |
iterates @var{n+1} times; @code{i} produces values starting with @var{n} |
and ending with 0. Other Forth systems may behave differently, even if |
and ending with 0. Other Forth systems may behave differently, even if |
they support @code{FOR} loops. |
they support @code{FOR} loops. |
Line 863 they support @code{FOR} loops.
|
Line 1307 they support @code{FOR} loops.
|
ANS Forth permits and supports using control structures in a non-nested |
ANS Forth permits and supports using control structures in a non-nested |
way. Information about incomplete control structures is stored on the |
way. Information about incomplete control structures is stored on the |
control-flow stack. This stack may be implemented on the Forth data |
control-flow stack. This stack may be implemented on the Forth data |
stack, and this is what we have done in gforth. |
stack, and this is what we have done in Gforth. |
|
|
An @i{orig} entry represents an unresolved forward branch, a @i{dest} |
An @i{orig} entry represents an unresolved forward branch, a @i{dest} |
entry represents a backward branch target. A few words are the basis for |
entry represents a backward branch target. A few words are the basis for |
Line 879 doc-again
|
Line 1323 doc-again
|
doc-cs-pick |
doc-cs-pick |
doc-cs-roll |
doc-cs-roll |
|
|
On many systems control-flow stack items take one word, in gforth they |
On many systems control-flow stack items take one word, in Gforth they |
currently take three (this may change in the future). Therefore it is a |
currently take three (this may change in the future). Therefore it is a |
really good idea to manipulate the control flow stack with |
really good idea to manipulate the control flow stack with |
@code{cs-pick} and @code{cs-roll}, not with data stack manipulation |
@code{cs-pick} and @code{cs-roll}, not with data stack manipulation |
Line 894 doc-repeat
|
Line 1338 doc-repeat
|
Counted loop words constitute a separate group of words: |
Counted loop words constitute a separate group of words: |
|
|
doc-?do |
doc-?do |
|
doc-+do |
|
doc-u+do |
|
doc--do |
|
doc-u-do |
doc-do |
doc-do |
doc-for |
doc-for |
doc-loop |
doc-loop |
doc-s+loop |
doc-s+loop |
doc-+loop |
doc-+loop |
|
doc--loop |
doc-next |
doc-next |
doc-leave |
doc-leave |
doc-?leave |
doc-?leave |
Line 969 necessary to define them.
|
Line 1418 necessary to define them.
|
@subsection Calls and returns |
@subsection Calls and returns |
|
|
A definition can be called simply be writing the name of the |
A definition can be called simply be writing the name of the |
definition. When the end of the definition is reached, it returns. An earlier return can be forced using |
definition. When the end of the definition is reached, it returns. An |
|
earlier return can be forced using |
|
|
doc-exit |
doc-exit |
|
|
Line 994 laden with restrictions. Therefore, we p
|
Line 1444 laden with restrictions. Therefore, we p
|
locals wordset, but also our own, more powerful locals wordset (we |
locals wordset, but also our own, more powerful locals wordset (we |
implemented the ANS Forth locals wordset through our locals wordset). |
implemented the ANS Forth locals wordset through our locals wordset). |
|
|
|
The ideas in this section have also been published in the paper |
|
@cite{Automatic Scoping of Local Variables} by M. Anton Ertl, presented |
|
at EuroForth '94; it is available at |
|
@*@file{http://www.complang.tuwien.ac.at/papers/ertl94l.ps.gz}. |
|
|
@menu |
@menu |
* gforth locals:: |
* Gforth locals:: |
* ANS Forth locals:: |
* ANS Forth locals:: |
@end menu |
@end menu |
|
|
@node gforth locals, ANS Forth locals, Locals, Locals |
@node Gforth locals, ANS Forth locals, Locals, Locals |
@subsection gforth locals |
@subsection Gforth locals |
|
|
Locals can be defined with |
Locals can be defined with |
|
|
Line 1043 The name of the local may be preceded by
|
Line 1498 The name of the local may be preceded by
|
Ar Bi f* Ai Br f* f+ ; |
Ar Bi f* Ai Br f* f+ ; |
@end example |
@end example |
|
|
GNU Forth currently supports cells (@code{W:}, @code{W^}), doubles |
Gforth currently supports cells (@code{W:}, @code{W^}), doubles |
(@code{D:}, @code{D^}), floats (@code{F:}, @code{F^}) and characters |
(@code{D:}, @code{D^}), floats (@code{F:}, @code{F^}) and characters |
(@code{C:}, @code{C^}) in two flavours: a value-flavoured local (defined |
(@code{C:}, @code{C^}) in two flavours: a value-flavoured local (defined |
with @code{W:}, @code{D:} etc.) produces its value and can be changed |
with @code{W:}, @code{D:} etc.) produces its value and can be changed |
Line 1063 locals are initialized with values from
|
Line 1518 locals are initialized with values from
|
Currently there is no way to define locals with user-defined data |
Currently there is no way to define locals with user-defined data |
structures, but we are working on it. |
structures, but we are working on it. |
|
|
GNU Forth allows defining locals everywhere in a colon definition. This |
Gforth allows defining locals everywhere in a colon definition. This |
poses the following questions: |
poses the following questions: |
|
|
@menu |
@menu |
Line 1073 poses the following questions:
|
Line 1528 poses the following questions:
|
* Implementation:: |
* Implementation:: |
@end menu |
@end menu |
|
|
@node Where are locals visible by name?, How long do locals live?, gforth locals, gforth locals |
@node Where are locals visible by name?, How long do locals live?, Gforth locals, Gforth locals |
@subsubsection Where are locals visible by name? |
@subsubsection Where are locals visible by name? |
|
|
Basically, the answer is that locals are visible where you would expect |
Basically, the answer is that locals are visible where you would expect |
Line 1195 If the @code{BEGIN} is not reachable fro
|
Line 1650 If the @code{BEGIN} is not reachable fro
|
@code{AHEAD} or @code{EXIT}), the compiler cannot even make an |
@code{AHEAD} or @code{EXIT}), the compiler cannot even make an |
optimistic guess, as the locals visible after the @code{BEGIN} may be |
optimistic guess, as the locals visible after the @code{BEGIN} may be |
defined later. Therefore, the compiler assumes that no locals are |
defined later. Therefore, the compiler assumes that no locals are |
visible after the @code{BEGIN}. However, the useer can use |
visible after the @code{BEGIN}. However, the user can use |
@code{ASSUME-LIVE} to make the compiler assume that the same locals are |
@code{ASSUME-LIVE} to make the compiler assume that the same locals are |
visible at the BEGIN as at the point where the item was created. |
visible at the BEGIN as at the point where the top control-flow stack |
|
item was created. |
|
|
doc-assume-live |
doc-assume-live |
|
|
Line 1231 WHILE
|
Line 1687 WHILE
|
REPEAT |
REPEAT |
@end example |
@end example |
|
|
@node How long do locals live?, Programming Style, Where are locals visible by name?, gforth locals |
@node How long do locals live?, Programming Style, Where are locals visible by name?, Gforth locals |
@subsubsection How long do locals live? |
@subsubsection How long do locals live? |
|
|
The right answer for the lifetime question would be: A local lives at |
The right answer for the lifetime question would be: A local lives at |
Line 1245 languages (e.g., C): The local lives onl
|
Line 1701 languages (e.g., C): The local lives onl
|
afterwards its address is invalid (and programs that access it |
afterwards its address is invalid (and programs that access it |
afterwards are erroneous). |
afterwards are erroneous). |
|
|
@node Programming Style, Implementation, How long do locals live?, gforth locals |
@node Programming Style, Implementation, How long do locals live?, Gforth locals |
@subsubsection Programming Style |
@subsubsection Programming Style |
|
|
The freedom to define locals anywhere has the potential to change |
The freedom to define locals anywhere has the potential to change |
Line 1259 write the items in the order you want.
|
Line 1715 write the items in the order you want.
|
This seems a little far-fetched and eliminating stack manipulations is |
This seems a little far-fetched and eliminating stack manipulations is |
unlikely to become a conscious programming objective. Still, the number |
unlikely to become a conscious programming objective. Still, the number |
of stack manipulations will be reduced dramatically if local variables |
of stack manipulations will be reduced dramatically if local variables |
are used liberally (e.g., compare @code{max} in @ref{gforth locals} with |
are used liberally (e.g., compare @code{max} in @ref{Gforth locals} with |
a traditional implementation of @code{max}). |
a traditional implementation of @code{max}). |
|
|
This shows one potential benefit of locals: making Forth programs more |
This shows one potential benefit of locals: making Forth programs more |
Line 1314 are initialized with the right value for
|
Line 1770 are initialized with the right value for
|
Here it is clear from the start that @code{s1} has a different value |
Here it is clear from the start that @code{s1} has a different value |
in every loop iteration. |
in every loop iteration. |
|
|
@node Implementation, , Programming Style, gforth locals |
@node Implementation, , Programming Style, Gforth locals |
@subsubsection Implementation |
@subsubsection Implementation |
|
|
GNU Forth uses an extra locals stack. The most compelling reason for |
Gforth uses an extra locals stack. The most compelling reason for |
this is that the return stack is not float-aligned; using an extra stack |
this is that the return stack is not float-aligned; using an extra stack |
also eliminates the problems and restrictions of using the return stack |
also eliminates the problems and restrictions of using the return stack |
as locals stack. Like the other stacks, the locals stack grows toward |
as locals stack. Like the other stacks, the locals stack grows toward |
Line 1352 area and @code{@}} switches it back and
|
Line 1808 area and @code{@}} switches it back and
|
initializing code. @code{W:} etc.@ are normal defining words. This |
initializing code. @code{W:} etc.@ are normal defining words. This |
special area is cleared at the start of every colon definition. |
special area is cleared at the start of every colon definition. |
|
|
A special feature of GNU Forths dictionary is used to implement the |
A special feature of Gforth's dictionary is used to implement the |
definition of locals without type specifiers: every wordlist (aka |
definition of locals without type specifiers: every wordlist (aka |
vocabulary) has its own methods for searching |
vocabulary) has its own methods for searching |
etc. (@pxref{Wordlists}). For the present purpose we defined a wordlist |
etc. (@pxref{Wordlists}). For the present purpose we defined a wordlist |
Line 1442 this may lead to increased space needs f
|
Line 1898 this may lead to increased space needs f
|
usually less than reclaiming this space would cost in code size. |
usually less than reclaiming this space would cost in code size. |
|
|
|
|
@node ANS Forth locals, , gforth locals, Locals |
@node ANS Forth locals, , Gforth locals, Locals |
@subsection ANS Forth locals |
@subsection ANS Forth locals |
|
|
The ANS Forth locals wordset does not define a syntax for locals, but |
The ANS Forth locals wordset does not define a syntax for locals, but |
words that make it possible to define various syntaxes. One of the |
words that make it possible to define various syntaxes. One of the |
possible syntaxes is a subset of the syntax we used in the gforth locals |
possible syntaxes is a subset of the syntax we used in the Gforth locals |
wordset, i.e.: |
wordset, i.e.: |
|
|
@example |
@example |
Line 1463 restrictions are:
|
Line 1919 restrictions are:
|
|
|
@itemize @bullet |
@itemize @bullet |
@item |
@item |
Locals can only be cell-sized values (no type specifers are allowed). |
Locals can only be cell-sized values (no type specifiers are allowed). |
@item |
@item |
Locals can be defined only outside control structures. |
Locals can be defined only outside control structures. |
@item |
@item |
Locals can interfere with explicit usage of the return stack. For the |
Locals can interfere with explicit usage of the return stack. For the |
exact (and long) rules, see the standard. If you don't use return stack |
exact (and long) rules, see the standard. If you don't use return stack |
accessing words in a definition using locals, you will we all right. The |
accessing words in a definition using locals, you will be all right. The |
purpose of this rule is to make locals implementation on the return |
purpose of this rule is to make locals implementation on the return |
stack easier. |
stack easier. |
@item |
@item |
Line 1480 Locals defined in this way behave like @
|
Line 1936 Locals defined in this way behave like @
|
(@xref{Values}). I.e., they are initialized from the stack. Using their |
(@xref{Values}). I.e., they are initialized from the stack. Using their |
name produces their value. Their value can be changed using @code{TO}. |
name produces their value. Their value can be changed using @code{TO}. |
|
|
Since this syntax is supported by gforth directly, you need not do |
Since this syntax is supported by Gforth directly, you need not do |
anything to use it. If you want to port a program using this syntax to |
anything to use it. If you want to port a program using this syntax to |
another ANS Forth system, use @file{anslocal.fs} to implement the syntax |
another ANS Forth system, use @file{anslocal.fs} to implement the syntax |
on the other system. |
on the other system. |
Line 1495 doc-(local)
|
Line 1951 doc-(local)
|
|
|
The ANS Forth locals extension wordset defines a syntax, but it is so |
The ANS Forth locals extension wordset defines a syntax, but it is so |
awful that we strongly recommend not to use it. We have implemented this |
awful that we strongly recommend not to use it. We have implemented this |
syntax to make porting to gforth easy, but do not document it here. The |
syntax to make porting to Gforth easy, but do not document it here. The |
problem with this syntax is that the locals are defined in an order |
problem with this syntax is that the locals are defined in an order |
reversed with respect to the standard stack comment notation, making |
reversed with respect to the standard stack comment notation, making |
programs harder to read, and easier to misread and miswrite. The only |
programs harder to read, and easier to misread and miswrite. The only |
Line 1524 locals wordset.
|
Line 1980 locals wordset.
|
@node Other I/O, Programming Tools, Blocks, Words |
@node Other I/O, Programming Tools, Blocks, Words |
@section Other I/O |
@section Other I/O |
|
|
@node Programming Tools, Threading Words, Other I/O, Words |
@node Programming Tools, Assembler and Code words, Other I/O, Words |
@section Programming Tools |
@section Programming Tools |
|
|
@menu |
@menu |
Line 1569 doc-printdebugline
|
Line 2025 doc-printdebugline
|
|
|
It is a good idea to make your programs self-checking, in particular, if |
It is a good idea to make your programs self-checking, in particular, if |
you use an assumption (e.g., that a certain field of a data structure is |
you use an assumption (e.g., that a certain field of a data structure is |
never zero) that may become wrong during maintenance. GForth supports |
never zero) that may become wrong during maintenance. Gforth supports |
assertions for this purpose. They are used like this: |
assertions for this purpose. They are used like this: |
|
|
@example |
@example |
Line 1592 debugging, we want more checking, in pro
|
Line 2048 debugging, we want more checking, in pro
|
for speed. Therefore, assertions can be turned off, i.e., the assertion |
for speed. Therefore, assertions can be turned off, i.e., the assertion |
becomes a comment. Depending on the importance of an assertion and the |
becomes a comment. Depending on the importance of an assertion and the |
time it takes to check it, you may want to turn off some assertions and |
time it takes to check it, you may want to turn off some assertions and |
keep others turned on. GForth provides several levels of assertions for |
keep others turned on. Gforth provides several levels of assertions for |
this purpose: |
this purpose: |
|
|
doc-assert0( |
doc-assert0( |
Line 1623 If there is interest, we will introduce
|
Line 2079 If there is interest, we will introduce
|
intend to @code{catch} a specific condition, using @code{throw} is |
intend to @code{catch} a specific condition, using @code{throw} is |
probably more appropriate than an assertion). |
probably more appropriate than an assertion). |
|
|
@node Threading Words, , Programming Tools, Words |
@node Assembler and Code words, Threading Words, Programming Tools, Words |
|
@section Assembler and Code words |
|
|
|
Gforth provides some words for defining primitives (words written in |
|
machine code), and for defining the the machine-code equivalent of |
|
@code{DOES>}-based defining words. However, the machine-independent |
|
nature of Gforth poses a few problems: First of all. Gforth runs on |
|
several architectures, so it can provide no standard assembler. What's |
|
worse is that the register allocation not only depends on the processor, |
|
but also on the gcc version and options used. |
|
|
|
The words Gforth offers encapsulate some system dependences (e.g., the |
|
header structure), so a system-independent assembler may be used in |
|
Gforth. If you do not have an assembler, you can compile machine code |
|
directly with @code{,} and @code{c,}. |
|
|
|
doc-assembler |
|
doc-code |
|
doc-end-code |
|
doc-;code |
|
doc-flush-icache |
|
|
|
If @code{flush-icache} does not work correctly, @code{code} words |
|
etc. will not work (reliably), either. |
|
|
|
These words are rarely used. Therefore they reside in @code{code.fs}, |
|
which is usually not loaded (except @code{flush-icache}, which is always |
|
present). You can load them with @code{require code.fs}. |
|
|
|
Another option for implementing normal and defining words efficiently |
|
is: adding the wanted functionality to the source of Gforth. For normal |
|
words you just have to edit @file{primitives}, defining words (for fast |
|
defined words) probably require changes in @file{engine.c}, |
|
@file{kernal.fs}, @file{prims2x.fs}, and possibly @file{cross.fs}. |
|
|
|
|
|
@node Threading Words, , Assembler and Code words, Words |
@section Threading Words |
@section Threading Words |
|
|
These words provide access to code addresses and other threading stuff |
These words provide access to code addresses and other threading stuff |
in gforth (and, possibly, other interpretive Forths). It more or less |
in Gforth (and, possibly, other interpretive Forths). It more or less |
abstracts away the differences between direct and indirect threading |
abstracts away the differences between direct and indirect threading |
(and, for direct threading, the machine dependences). However, at |
(and, for direct threading, the machine dependences). However, at |
present this wordset is still inclomplete. It is also pretty low-level; |
present this wordset is still inclomplete. It is also pretty low-level; |
Line 1641 doc-does-code!
|
Line 2133 doc-does-code!
|
doc-does-handler! |
doc-does-handler! |
doc-/does-handler |
doc-/does-handler |
|
|
|
The code addresses produced by various defining words are produced by |
|
the following words: |
|
|
|
doc-docol: |
|
doc-docon: |
|
doc-dovar: |
|
doc-douser: |
|
doc-dodefer: |
|
doc-dofield: |
|
|
|
Currently there is no installation-independent way for recogizing words |
|
defined by a @code{CREATE}...@code{DOES>} word; however, once you know |
|
that a word is defined by a @code{CREATE}...@code{DOES>} word, you can |
|
use @code{>DOES-CODE}. |
|
|
@node ANS conformance, Model, Words, Top |
@node ANS conformance, Model, Words, Top |
@chapter ANS conformance |
@chapter ANS conformance |
|
|
To the best of our knowledge, gforth is an |
To the best of our knowledge, Gforth is an |
|
|
ANS Forth System |
ANS Forth System |
@itemize |
@itemize |
Line 1668 ANS Forth System
|
Line 2173 ANS Forth System
|
@item providing the Memory-Allocation word set |
@item providing the Memory-Allocation word set |
@item providing the Memory-Allocation Extensions word set (that one's easy) |
@item providing the Memory-Allocation Extensions word set (that one's easy) |
@item providing the Programming-Tools word set |
@item providing the Programming-Tools word set |
@item providing @code{AHEAD}, @code{BYE}, @code{CS-PICK}, @code{CS-ROLL}, @code{STATE}, @code{[ELSE]}, @code{[IF]}, @code{[THEN]} from the Programming-Tools Extensions word set |
@item providing @code{;code}, @code{AHEAD}, @code{ASSEMBLER}, @code{BYE}, @code{CODE}, @code{CS-PICK}, @code{CS-ROLL}, @code{STATE}, @code{[ELSE]}, @code{[IF]}, @code{[THEN]} from the Programming-Tools Extensions word set |
@item providing the Search-Order word set |
@item providing the Search-Order word set |
@item providing the Search-Order Extensions word set |
@item providing the Search-Order Extensions word set |
@item providing the String word set |
@item providing the String word set |
Line 1681 requirements. In many cases it gives a w
|
Line 2186 requirements. In many cases it gives a w
|
information instead of providing the information directly, in |
information instead of providing the information directly, in |
particular, if the information depends on the processor, the operating |
particular, if the information depends on the processor, the operating |
system or the installation options chosen, or if they are likely to |
system or the installation options chosen, or if they are likely to |
change during the maintenance of gforth. |
change during the maintenance of Gforth. |
|
|
@comment The framework for the rest has been taken from pfe. |
@comment The framework for the rest has been taken from pfe. |
|
|
Line 1720 change during the maintenance of gforth.
|
Line 2225 change during the maintenance of gforth.
|
@table @i |
@table @i |
|
|
@item (Cell) aligned addresses: |
@item (Cell) aligned addresses: |
processor-dependent. Gforths alignment words perform natural alignment |
processor-dependent. Gforth's alignment words perform natural alignment |
(e.g., an address aligned for a datum of size 8 is divisible by |
(e.g., an address aligned for a datum of size 8 is divisible by |
8). Unaligned accesses usually result in a @code{-23 THROW}. |
8). Unaligned accesses usually result in a @code{-23 THROW}. |
|
|
Line 1745 installation-dependent. Currently a char
|
Line 2250 installation-dependent. Currently a char
|
(Comments on that requested). |
(Comments on that requested). |
|
|
@item character-set extensions and matching of names: |
@item character-set extensions and matching of names: |
Any character except 0 can be used in a name. Matching is |
Any character except the ASCII NUL charcter can be used in a |
case-insensitive. The matching is performed using the C function |
name. Matching is case-insensitive. The matching is performed using the |
@code{strncasecmp}, whose function is probably influenced by the |
C function @code{strncasecmp}, whose function is probably influenced by |
locale. E.g., the @code{C} locale does not know about accents and |
the locale. E.g., the @code{C} locale does not know about accents and |
umlauts, so they are matched case-sensitively in that locale. For |
umlauts, so they are matched case-sensitively in that locale. For |
portability reasons it is best to write programs such that they work in |
portability reasons it is best to write programs such that they work in |
the @code{C} locale. Then one can use libraries written by a Polish |
the @code{C} locale. Then one can use libraries written by a Polish |
Line 1808 Given by the constant @code{/line}. Curr
|
Line 2313 Given by the constant @code{/line}. Curr
|
31 |
31 |
|
|
@item method of selecting the user input device: |
@item method of selecting the user input device: |
The user input device is the standard input. There is current no way to |
The user input device is the standard input. There is currently no way to |
change it from within gforth. However, the input can typically be |
change it from within Gforth. However, the input can typically be |
redirected in the command line that starts gforth. |
redirected in the command line that starts Gforth. |
|
|
@item method of selecting the user output device: |
@item method of selecting the user output device: |
The user output device is the standard output. It cannot be redirected |
The user output device is the standard output. It cannot be redirected |
from within gforth, but typically from the command line that starts |
from within Gforth, but typically from the command line that starts |
gforth. Gforth uses buffered output, so output on a terminal does not |
Gforth. Gforth uses buffered output, so output on a terminal does not |
become visible before the next newline or buffer overflow. Output on |
become visible before the next newline or buffer overflow. Output on |
non-terminals is invisible until the buffer overflows. |
non-terminals is invisible until the buffer overflows. |
|
|
@item methods of dictionary compilation: |
@item methods of dictionary compilation: |
Waht are we expected to document here? |
What are we expected to document here? |
|
|
@item number of bits in one address unit: |
@item number of bits in one address unit: |
@code{s" address-units-bits" environment? drop .}. 8 in all current |
@code{s" address-units-bits" environment? drop .}. 8 in all current |
Line 1856 string.
|
Line 2361 string.
|
Varies. You can determine the size at a specific time using @code{lp@ |
Varies. You can determine the size at a specific time using @code{lp@ |
tib - .}. It is shared with the locals stack and TIBs of files that |
tib - .}. It is shared with the locals stack and TIBs of files that |
include the current file. You can change the amount of space for TIBs |
include the current file. You can change the amount of space for TIBs |
and locals stack at gforth startup with the command line option |
and locals stack at Gforth startup with the command line option |
@code{-l}. |
@code{-l}. |
|
|
@item size of the pictured numeric output buffer: |
@item size of the pictured numeric output buffer: |
Line 1991 Compiles a recursive call to the definin
|
Line 2496 Compiles a recursive call to the definin
|
|
|
@item argument input source different than current input source for @code{RESTORE-INPUT}: |
@item argument input source different than current input source for @code{RESTORE-INPUT}: |
!!???If the argument input source is a valid input source then it gets |
!!???If the argument input source is a valid input source then it gets |
restored. Otherwise causes @code{-12 THROW} which unless caught issues |
restored. Otherwise causes @code{-12 THROW}, which, unless caught, issues |
the message "argument type mismatch" and aborts. |
the message "argument type mismatch" and aborts. |
|
|
@item data space containing definitions gets de-allocated: |
@item data space containing definitions gets de-allocated: |
Line 2234 another question.
|
Line 2739 another question.
|
|
|
@item repeatability to be expected from the execution of @code{MS}: |
@item repeatability to be expected from the execution of @code{MS}: |
System dependent. On Unix, a lot depends on load. If the system is |
System dependent. On Unix, a lot depends on load. If the system is |
lightly loaded, and the delay is short enough that gforth does not get |
lightly loaded, and the delay is short enough that Gforth does not get |
swapped out, the performance should be acceptable. Under MS-DOS and |
swapped out, the performance should be acceptable. Under MS-DOS and |
other single-tasking systems, it should be good. |
other single-tasking systems, it should be good. |
|
|
Line 2665 when @code{REVEAL} is executed (by @code
|
Line 3170 when @code{REVEAL} is executed (by @code
|
@end table |
@end table |
|
|
|
|
@node Model, Emacs and GForth, ANS conformance, Top |
@node Model, Emacs and Gforth, ANS conformance, Top |
@chapter Model |
@chapter Model |
|
|
@node Emacs and GForth, Internals, Model, Top |
@node Emacs and Gforth, Internals, Model, Top |
@chapter Emacs and GForth |
@chapter Emacs and Gforth |
|
|
GForth comes with @file{gforth.el}, an improved version of |
Gforth comes with @file{gforth.el}, an improved version of |
@file{forth.el} by Goran Rydqvist (icluded in the TILE package). The |
@file{forth.el} by Goran Rydqvist (icluded in the TILE package). The |
improvements are a better (but still not perfect) handling of |
improvements are a better (but still not perfect) handling of |
indentation. I have also added comment paragraph filling (@kbd{M-q}), |
indentation. I have also added comment paragraph filling (@kbd{M-q}), |
Line 2681 stuff I do not use alone, even though so
|
Line 3186 stuff I do not use alone, even though so
|
TILE. To get a description of these features, enter Forth mode and type |
TILE. To get a description of these features, enter Forth mode and type |
@kbd{C-h m}. |
@kbd{C-h m}. |
|
|
In addition, GForth supports Emacs quite well: The source code locations |
In addition, Gforth supports Emacs quite well: The source code locations |
given in error messages, debugging output (from @code{~~}) and failed |
given in error messages, debugging output (from @code{~~}) and failed |
assertion messages are in the right format for Emacs' compilation mode |
assertion messages are in the right format for Emacs' compilation mode |
(@pxref{Compilation, , Running Compilations under Emacs, emacs, Emacs |
(@pxref{Compilation, , Running Compilations under Emacs, emacs, Emacs |
Line 2693 Also, if you @code{include} @file{etags.
|
Line 3198 Also, if you @code{include} @file{etags.
|
(@pxref{Tags, , Tags Tables, emacs, Emacs Manual}) will be produced that |
(@pxref{Tags, , Tags Tables, emacs, Emacs Manual}) will be produced that |
contains the definitions of all words defined afterwards. You can then |
contains the definitions of all words defined afterwards. You can then |
find the source for a word using @kbd{M-.}. Note that emacs can use |
find the source for a word using @kbd{M-.}. Note that emacs can use |
several tags files at the same time (e.g., one for the gforth sources |
several tags files at the same time (e.g., one for the Gforth sources |
and one for your program). |
and one for your program). |
|
|
To get all these benefits, add the following lines to your @file{.emacs} |
To get all these benefits, add the following lines to your @file{.emacs} |
Line 2704 file:
|
Line 3209 file:
|
(setq auto-mode-alist (cons '("\\.fs\\'" . forth-mode) auto-mode-alist)) |
(setq auto-mode-alist (cons '("\\.fs\\'" . forth-mode) auto-mode-alist)) |
@end example |
@end example |
|
|
@node Internals, Bugs, Emacs and GForth, Top |
@node Internals, Bugs, Emacs and Gforth, Top |
@chapter Internals |
@chapter Internals |
|
|
Reading this section is not necessary for programming with gforth. It |
Reading this section is not necessary for programming with Gforth. It |
should be helpful for finding your way in the gforth sources. |
should be helpful for finding your way in the Gforth sources. |
|
|
|
The ideas in this section have also been published in the papers |
|
@cite{ANS fig/GNU/??? Forth} (in German) by Bernd Paysan, presented at |
|
the Forth-Tagung '93 and @cite{A Portable Forth Engine} by M. Anton |
|
Ertl, presented at EuroForth '93; the latter is available at |
|
@*@file{http://www.complang.tuwien.ac.at/papers/ertl93.ps.Z}. |
|
|
@menu |
@menu |
* Portability:: |
* Portability:: |
* Threading:: |
* Threading:: |
* Primitives:: |
* Primitives:: |
* System Architecture:: |
* System Architecture:: |
|
* Performance:: |
@end menu |
@end menu |
|
|
@node Portability, Threading, Internals, Internals |
@node Portability, Threading, Internals, Internals |
Line 2746 Double-Word Integers, gcc.info, GNU C Ma
|
Line 3258 Double-Word Integers, gcc.info, GNU C Ma
|
double numbers. GNU C is available for free on all important (and many |
double numbers. GNU C is available for free on all important (and many |
unimportant) UNIX machines, VMS, 80386s running MS-DOS, the Amiga, and |
unimportant) UNIX machines, VMS, 80386s running MS-DOS, the Amiga, and |
the Atari ST, so a Forth written in GNU C can run on all these |
the Atari ST, so a Forth written in GNU C can run on all these |
machines@footnote{Due to Apple's look-and-feel lawsuit it is not |
machines. |
available on the Mac (@pxref{Boycott, , Protect Your Freedom---Fight |
|
``Look And Feel'', gcc.info, GNU C Manual}).}. |
|
|
|
Writing in a portable language has the reputation of producing code that |
Writing in a portable language has the reputation of producing code that |
is slower than assembly. For our Forth engine we repeatedly looked at |
is slower than assembly. For our Forth engine we repeatedly looked at |
Line 3039 To see what assembly code is produced fo
|
Line 3549 To see what assembly code is produced fo
|
with your compiler and your flag settings, type @code{make engine.s} and |
with your compiler and your flag settings, type @code{make engine.s} and |
look at the resulting file @file{engine.s}. |
look at the resulting file @file{engine.s}. |
|
|
@node System Architecture, , Primitives, Internals |
@node System Architecture, Performance, Primitives, Internals |
@section System Architecture |
@section System Architecture |
|
|
Our Forth system consists not only of primitives, but also of |
Our Forth system consists not only of primitives, but also of |
Line 3062 possible, because we do not want to dist
|
Line 3572 possible, because we do not want to dist
|
same image file, and to make it easy for the users to use their image |
same image file, and to make it easy for the users to use their image |
files on many machines. We currently need to create a different image |
files on many machines. We currently need to create a different image |
file for machines with different cell sizes and different byte order |
file for machines with different cell sizes and different byte order |
(little- or big-endian)@footnote{We consider adding information to the |
(little- or big-endian)@footnote{We are considering adding information to the |
image file that enables the loader to change the byte order.}. |
image file that enables the loader to change the byte order.}. |
|
|
Forth code that is going to end up in a portable image file has to |
Forth code that is going to end up in a portable image file has to |
Line 3082 at run-time. The loader also has to repl
|
Line 3592 at run-time. The loader also has to repl
|
primitive calls with the appropriate code-field addresses (or code |
primitive calls with the appropriate code-field addresses (or code |
addresses in the case of direct threading). |
addresses in the case of direct threading). |
|
|
|
@node Performance, , System Architecture, Internals |
|
@section Performance |
|
|
|
On RISCs the Gforth engine is very close to optimal; i.e., it is usually |
|
impossible to write a significantly faster engine. |
|
|
|
On register-starved machines like the 386 architecture processors |
|
improvements are possible, because @code{gcc} does not utilize the |
|
registers as well as a human, even with explicit register declarations; |
|
e.g., Bernd Beuster wrote a Forth system fragment in assembly language |
|
and hand-tuned it for the 486; this system is 1.19 times faster on the |
|
Sieve benchmark on a 486DX2/66 than Gforth compiled with |
|
@code{gcc-2.6.3} with @code{-DFORCE_REG}. |
|
|
|
However, this potential advantage of assembly language implementations |
|
is not necessarily realized in complete Forth systems: We compared |
|
Gforth (compiled with @code{gcc-2.6.3} and @code{-DFORCE_REG}) with |
|
Win32Forth 1.2093 and LMI's NT Forth (Beta, May 1994), two systems |
|
written in assembly, and with two systems written in C: PFE-0.9.11 |
|
(compiled with @code{gcc-2.6.3} with the default configuration for |
|
Linux: @code{-O2 -fomit-frame-pointer -DUSE_REGS}) and ThisForth Beta |
|
(compiled with gcc-2.6.3 -O3 -fomit-frame-pointer). We benchmarked |
|
Gforth, PFE and ThisForth on a 486DX2/66 under Linux. Kenneth O'Heskin |
|
kindly provided the results for Win32Forth and NT Forth on a 486DX2/66 |
|
with similar memory performance under Windows NT. |
|
|
|
We used four small benchmarks: the ubiquitous Sieve; bubble-sorting and |
|
matrix multiplication come from the Stanford integer benchmarks and have |
|
been translated into Forth by Martin Fraeman; we used the versions |
|
included in the TILE Forth package; and a recursive Fibonacci number |
|
computation for benchmarking calling performance. The following table shows |
|
the time taken for the benchmarks scaled by the time taken by Gforth (in |
|
other words, it shows the speedup factor that Gforth achieved over the |
|
other systems). |
|
|
|
@example |
|
relative Win32- NT This- |
|
time Gforth Forth Forth PFE Forth |
|
sieve 1.00 1.30 1.07 1.67 2.98 |
|
bubble 1.00 1.30 1.40 1.66 |
|
matmul 1.00 1.40 1.29 2.24 |
|
fib 1.00 1.44 1.26 1.82 2.82 |
|
@end example |
|
|
|
You may find the good performance of Gforth compared with the systems |
|
written in assembly language quite surprising. One important reason for |
|
the disappointing performance of these systems is probably that they are |
|
not written optimally for the 486 (e.g., they use the @code{lods} |
|
instruction). In addition, Win32Forth uses a comfortable, but costly |
|
method for relocating the Forth image: like @code{cforth}, it computes |
|
the actual addresses at run time, resulting in two address computations |
|
per NEXT (@pxref{System Architecture}). |
|
|
|
The speedup of Gforth over PFE and ThisForth can be easily explained |
|
with the self-imposed restriction to standard C (although the measured |
|
implementation of PFE uses a GNU C extension: global register |
|
variables), which makes efficient threading impossible. Moreover, |
|
current C compilers have a hard time optimizing other aspects of the |
|
ThisForth source. |
|
|
|
Note that the performance of Gforth on 386 architecture processors |
|
varies widely with the version of @code{gcc} used. E.g., @code{gcc-2.5.8} |
|
failed to allocate any of the virtual machine registers into real |
|
machine registers by itself and would not work correctly with explicit |
|
register declarations, giving a 1.3 times slower engine (on a 486DX2/66 |
|
running the Sieve) than the one measured above. |
|
|
|
The numbers in this section have also been published in the paper |
|
@cite{Translating Forth to Efficient C} by M. Anton Ertl and Martin |
|
Maierhofer, presented at EuroForth '95. It is available at |
|
@*@file{http://www.complang.tuwien.ac.at/papers/ertl&maierhofer95.ps.gz}; |
|
it also contains numbers for some native code systems. You can find |
|
numbers for Gforth on various machines in @file{Benchres}. |
|
|
@node Bugs, Pedigree, Internals, Top |
@node Bugs, Pedigree, Internals, Top |
@chapter Bugs |
@chapter Bugs |
|
|
|
Known bugs are described in the file BUGS in the Gforth distribution. |
|
|
|
If you find a bug, please send a bug report to |
|
@code{gforth-bugs@@mips.complang.tuwien.ac.at}. A bug report should |
|
describe the Gforth version used (it is announced at the start of an |
|
interactive Gforth session), the machine and operating system (on Unix |
|
systems you can use @code{uname -a} to produce this information), the |
|
installation options (send the @code{config.status} file), and a |
|
complete list of changes you (or your installer) have made to the Gforth |
|
sources (if any); it should contain a program (or a sequence of keyboard |
|
commands) that reproduces the bug and a description of what you think |
|
constitutes the buggy behaviour. |
|
|
|
For a thorough guide on reporting bugs read @ref{Bug Reporting, , How |
|
to Report Bugs, gcc.info, GNU C Manual}. |
|
|
|
|
@node Pedigree, Word Index, Bugs, Top |
@node Pedigree, Word Index, Bugs, Top |
@chapter Pedigree |
@chapter Pedigree |
|
|
|
Gforth descends from BigForth (1993) and fig-Forth. Gforth and PFE (by |
|
Dirk Zoller) will cross-fertilize each other. Of course, a significant |
|
part of the design of Gforth was prescribed by ANS Forth. |
|
|
|
Bernd Paysan wrote BigForth, a descendent from TurboForth, an unreleased |
|
32 bit native code version of VolksForth for the Atari ST, written |
|
mostly by Dietrich Weineck. |
|
|
|
VolksForth descends from F83. It was written by Klaus Schleisiek, Bernd |
|
Pennemann, Georg Rehfeld and Dietrich Weineck for the C64 (called |
|
UltraForth there) in the mid-80s and ported to the Atari ST in 1986. |
|
|
|
Laxen and Perry wrote F83 as a model implementation of the |
|
Forth-83 standard. !! Pedigree? When? |
|
|
|
A team led by Bill Ragsdale implemented fig-Forth on many processors in |
|
1979. Robert Selzer and Bill Ragsdale developed the original |
|
implementation of fig-Forth for the 6502 based on microForth. |
|
|
|
The principal architect of microForth was Dean Sanderson. microForth was |
|
FORTH, Inc.'s first off-the-shelf product. It was developped in 1976 for |
|
the 1802, and subsequently implemented on the 8080, the 6800 and the |
|
Z80. |
|
|
|
All earlier Forth systems were custom-made, usually by Charles Moore, |
|
who discovered (as he puts it) Forth in the late 60s. |
|
|
|
A part of the information in this section comes from @cite{The Evolution |
|
of Forth} by Elizabeth D. Rather, Donald R. Colburn and Charles |
|
H. Moore, presented at the HOPL-II conference and preprinted in SIGPLAN |
|
Notices 28(3), 1993. You can find more historical and genealogical |
|
information about Forth there. |
|
|
@node Word Index, Node Index, Pedigree, Top |
@node Word Index, Node Index, Pedigree, Top |
@chapter Word Index |
@chapter Word Index |
|
|
|
This index is as incomplete as the manual. Each word is listed with |
|
stack effect and wordset. |
|
|
|
@printindex fn |
|
|
@node Node Index, , Word Index, Top |
@node Node Index, , Word Index, Top |
@chapter Node Index |
@chapter Node Index |
|
|
|
This index is even less complete than the manual. |
|
|
@contents |
@contents |
@bye |
@bye |
|
|