--- gforth/Attic/gforth.ds 1995/09/15 14:52:51 1.17 +++ gforth/Attic/gforth.ds 1995/11/28 18:45:28 1.25 @@ -9,7 +9,7 @@ @ifinfo This file documents Gforth 0.1 -Copyright @copyright{} 1994 Gforth Development Group +Copyright @copyright{} 1995 Free Software Foundation, Inc. Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice @@ -36,6 +36,7 @@ Copyright @copyright{} 1994 Gforth Devel of in the original English. @end ifinfo +@finalout @titlepage @sp 10 @center @titlefont{Gforth Manual} @@ -43,13 +44,14 @@ Copyright @copyright{} 1994 Gforth Devel @center for version 0.1 @sp 2 @center Anton Ertl +@center Bernd Paysan @sp 3 @center This manual is under construction @comment The following two commands start the copyright page. @page @vskip 0pt plus 1filll -Copyright @copyright{} 1994 Gforth Development Group +Copyright @copyright{} 1995 Free Software Foundation, Inc. @comment !! Published by ... or You can get a copy of this manual ... @@ -75,7 +77,7 @@ Copyright @copyright{} 1994 Gforth Devel @node Top, License, (dir), (dir) @ifinfo 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 @menu @@ -95,11 +97,402 @@ personal machines. This manual correspon @end menu @node License, Goals, Top, Top -@unnumbered License -!! Insert GPL here +@unnumbered GNU GENERAL PUBLIC LICENSE +@center Version 2, June 1991 + +@display +Copyright @copyright{} 1989, 1991 Free Software Foundation, Inc. +675 Mass Ave, Cambridge, MA 02139, USA + +Everyone is permitted to copy and distribute verbatim copies +of this license document, but changing it is not allowed. +@end display + +@unnumberedsec Preamble + + The licenses for most software are designed to take away your +freedom to share and change it. By contrast, the GNU General Public +License is intended to guarantee your freedom to share and change free +software---to make sure the software is free for all its users. This +General Public License applies to most of the Free Software +Foundation's software and to any other program whose authors commit to +using it. (Some other Free Software Foundation software is covered by +the GNU Library General Public License instead.) You can apply it to +your programs, too. + + When we speak of free software, we are referring to freedom, not +price. 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For software which is copyrighted by the Free +Software Foundation, write to the Free Software Foundation; we sometimes +make exceptions for this. Our decision will be guided by the two goals +of preserving the free status of all derivatives of our free software and +of promoting the sharing and reuse of software generally. + +@iftex +@heading NO WARRANTY +@end iftex +@ifinfo +@center NO WARRANTY +@end ifinfo + +@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 +PROVIDE THE PROGRAM ``AS IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED +OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF +MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS +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. + +@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 + +@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 +@cindex Preface This manual documents Gforth. The reader is expected to know Forth. This manual is primarily a reference manual. @xref{Other Books} for introductory material. @@ -157,12 +550,19 @@ not written for ANS Forth, as you will n deviations of the book. 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 -Global Engineering Documents !! somtime in spring or summer 1994. If you -are lucky, you can still get dpANS6 (the draft that was approved as -standard) by aftp from ftp.uu.net:/vendor/minerva/x3j14. +write ANS Forth programs. It is available in printed form from the +National Standards Institute Sales Department (Tel.: USA (212) 642-4900; +Fax.: USA (212) 302-1286) as document @cite{X3.215-1994} for about $200. You +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 cover the whole standard. It also contains interesting background information (Jack Woehr was in the ANS Forth Technical Committe). It is @@ -193,10 +593,12 @@ line. They are: @table @code @item --image-file @var{file} +@item -i @var{file} Loads the Forth image @var{file} instead of the default @file{gforth.fi}. @item --path @var{path} +@item -p @var{path} Uses @var{path} for searching the image file and Forth source code files instead of the default in the environment variable @code{GFORTHPATH} or the path specified at installation time (typically @@ -245,6 +647,12 @@ Forth words, you have to quote them or u after processing the command line (instead of entering interactive mode) 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: On startup the system first executes the system initialization file (unless the option @code{--no-init-file} is given; note that the system @@ -269,6 +677,7 @@ then in @file{~}, then in the normal pat * Blocks:: * Other I/O:: * Programming Tools:: +* Assembler and Code words:: * Threading Words:: @end menu @@ -300,6 +709,13 @@ effect}, but in @var{Description}. The n the type and/or the function of the item. See below for a discussion of 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 How the word is pronounced @@ -309,7 +725,11 @@ system need not support all of them. So, uses the more portable it will be in theory. However, we suspect that most ANS Forth systems on personal machines will feature all 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 A description of the behaviour of the word. @@ -808,13 +1228,27 @@ There are several variations on the coun @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 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.: -@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: @@ -822,23 +1256,34 @@ The behaviour of @code{@var{n} +LOOP} is @code{ 0 0 ?DO i . -1 +LOOP} prints nothing -Therefore we recommend avoiding using @code{@var{n} +LOOP} with negative -@var{n}. One alternative is @code{@var{n} S+LOOP}, where the negative -case behaves symmetrical to the positive case: +Therefore we recommend avoiding @code{@var{n} +LOOP} with negative +@var{n}. One alternative is @code{@var{u} -LOOP}, which reduces the +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 -@var{limit} is crossed. However, @code{S+LOOP} is not part of the ANS -Forth standard. +Another alternative is @code{@var{n} S+LOOP}, where the negative +case behaves symmetrical to the positive case: -@code{?DO} can be replaced by @code{DO}. @code{DO} enters the loop even -when the start and the limit value are equal. We do not recommend using -@code{DO}. It will just give you maintenance troubles. +@code{-2 0 -DO i . -1 S+LOOP} prints @code{0 -1} + +The loop is terminated when the border between @var{limit@minus{}sgn(n)} +and @var{limit} is crossed. Unfortunately, neither @code{-LOOP} nor +@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{EXIT}. @code{UNLOOP} removes the loop control parameters from the @@ -894,11 +1339,16 @@ doc-repeat Counted loop words constitute a separate group of words: doc-?do +doc-+do +doc-u+do +doc--do +doc-u-do doc-do doc-for doc-loop doc-s+loop doc-+loop +doc--loop doc-next doc-leave doc-?leave @@ -995,6 +1445,11 @@ laden with restrictions. Therefore, we p locals wordset, but also our own, more powerful locals wordset (we 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 * Gforth locals:: * ANS Forth locals:: @@ -1526,7 +1981,7 @@ locals wordset. @node Other I/O, Programming Tools, Blocks, Words @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 @menu @@ -1625,7 +2080,75 @@ If there is interest, we will introduce intend to @code{catch} a specific condition, using @code{throw} is 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 @code{gcc} version and options used. + +The words that 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}. + +In the assembly code you will want to refer to the inner interpreter's +registers (e.g., the data stack pointer) and you may want to use other +registers for temporary storage. Unfortunately, the register allocation +is installation-dependent. + +The easiest solution is to use explicit register declarations +(@pxref{Explicit Reg Vars, , Variables in Specified Registers, gcc.info, +GNU C Manual}) for all of the inner interpreter's registers: You have to +compile Gforth with @code{-DFORCE_REG} (configure option +@code{--enable-force-reg}) and the appropriate declarations must be +present in the @code{machine.h} file (see @code{mips.h} for an example; +you can find a full list of all declarable register symbols with +@code{grep register engine.c}). If you give explicit registers to all +variables that are declared at the beginning of @code{engine()}, you +should be able to use the other caller-saved registers for temporary +storage. Alternatively, you can use the @code{gcc} option +@code{-ffixed-REG} (@pxref{Code Gen Options, , Options for Code +Generation Conventions, gcc.info, GNU C Manual}) to reserve a register +(however, this restriction on register allocation may slow Gforth +significantly). + +If this solution is not viable (e.g., because @code{gcc} does not allow +you to explicitly declare all the registers you need), you have to find +out by looking at the code where the inner interpreter's registers +reside and which registers can be used for temporary storage. You can +get an assembly listing of the engine's code with @code{make engine.s}. + +In any case, it is good practice to abstract your assembly code from the +actual register allocation. E.g., if the data stack pointer resides in +register @code{$17}, create an alias for this register called @code{sp}, +and use that in your assembly code. + +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) may 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 These words provide access to code addresses and other threading stuff @@ -1643,7 +2166,20 @@ doc-does-code! 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 @chapter ANS conformance @@ -1670,7 +2206,7 @@ ANS Forth System @item providing the Memory-Allocation word set @item providing the Memory-Allocation Extensions word set (that one's easy) @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 Extensions word set @item providing the String word set @@ -1881,7 +2417,7 @@ characters is determined by the locale y @item division rounding: installation dependent. @code{s" floored" environment? drop .}. We leave -the choice to gcc (what to use for @code{/}) and to you (whether to use +the choice to @code{gcc} (what to use for @code{/}) and to you (whether to use @code{fm/mod}, @code{sm/rem} or simply @code{/}). @item values of @code{STATE} when true: @@ -1993,7 +2529,7 @@ Compiles a recursive call to the definin @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 -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. @item data space containing definitions gets de-allocated: @@ -2712,6 +3248,12 @@ file: Reading this section is not necessary for programming with Gforth. It 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 * Portability:: * Threading:: @@ -3100,20 +3642,20 @@ Sieve benchmark on a 486DX2/66 than Gfor 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 and LMI's NT Forth, 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. +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 benchmark calling performance. The following table shows +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). @@ -3150,20 +3692,28 @@ machine registers by itself and would no 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 @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 !!. A bug report should +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 (!! a way to find them out), 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. +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}. @@ -3173,20 +3723,31 @@ to Report Bugs, gcc.info, GNU C Manual}. @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. +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 child of VolksForth. +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. -VolksForth descends from F83. !! Authors? When? - -Laxen and Perry wrote F83 as a model implementation of the +Hennry Laxen and Mike 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. Dean Sanderson and Bill Ragsdale developed the original -implementation of fig-Forth based on microForth. +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. -!! microForth pedigree +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 @@ -3197,7 +3758,8 @@ information about Forth there. @node Word Index, Node Index, Pedigree, Top @chapter Word Index -This index is as incomplete as the manual. +This index is as incomplete as the manual. Each word is listed with +stack effect and wordset. @printindex fn