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Diff for /gforth/doc/gforth.ds between versions 1.59 and 1.60

version 1.59, 2000/07/16 20:09:37 version 1.60, 2000/07/17 15:26:32
Line 1901  In this case the stack comment is pretty Line 1901  In this case the stack comment is pretty
 is simple enough.  If you think it would be a good idea to add such a  is simple enough.  If you think it would be a good idea to add such a
 comment to increase readability, you should also consider factoring the  comment to increase readability, you should also consider factoring the
 word into several simpler words (@pxref{Factoring Tutorial,,  word into several simpler words (@pxref{Factoring Tutorial,,
 Factoring}), which typically eliminates the need for the stack effect;  Factoring}), which typically eliminates the need for the stack comment;
 however, if you decide not to refactor it, then having such a comment is  however, if you decide not to refactor it, then having such a comment is
 better than not having it.  better than not having it.
   
Line 2200  Comparison words produce canonical flags Line 2200  Comparison words produce canonical flags
   
 Gforth supports all combinations of the prefixes @code{0 u d d0 du} (or  Gforth supports all combinations of the prefixes @code{0 u d d0 du} (or
 none) and the comparisons @code{= <> < > <= >=}.  Only a part of these  none) and the comparisons @code{= <> < > <= >=}.  Only a part of these
 combinations are standard (see the standard or !! the glossary for  combinations are standard (for details see the standard or @ref{Word
 details).  Glossary}).
   
 You can use @code{and or xor invert} can be used as operations on  You can use @code{and or xor invert} can be used as operations on
 canonical flags.  Actually they are bitwise operations:  canonical flags.  Actually they are bitwise operations:
Line 2553  one at @code{addr cell+} etc. Line 2553  one at @code{addr cell+} etc.
 You can also reserve memory without creating a new word:  You can also reserve memory without creating a new word:
   
 @example  @example
 here 10 cells allot  here 10 cells allot .
 .s  here .
 @end example  @end example
   
 @code{Here} pushes the start address of the memory area.  You should  @code{Here} pushes the start address of the memory area.  You should
Line 2568  you have just @code{allot}ed with Line 2568  you have just @code{allot}ed with
   
 @example  @example
 -10 cells allot  -10 cells allot
   here .
 @end example  @end example
   
 Note that you cannot do this if you have created a new word in the  Note that you cannot do this if you have created a new word in the
Line 2587  free throw Line 2588  free throw
   
 The @code{throw}s deal with errors (e.g., out of memory).  The @code{throw}s deal with errors (e.g., out of memory).
   
 And there is also a garbage collector @url{!!}, which eliminates the  And there is also a garbage collector
 need to @code{free} memory explicitly.  @url{http://www.complang.tuwien.ac.at/forth/garbage-collection.zip},
   which eliminates the need to @code{free} memory explicitly.
   
   
 @node Characters and Strings Tutorial, Alignment Tutorial, Memory Tutorial, Tutorial  @node Characters and Strings Tutorial, Alignment Tutorial, Memory Tutorial, Tutorial
Line 2831  see foo Line 2833  see foo
 : bar ( ... "word" -- ... )  : bar ( ... "word" -- ... )
   ' execute ;    ' execute ;
 see bar  see bar
 1 2 bar +  1 2 bar + .
 @end example  @end example
   
 You often want to parse a word during compilation and compile its XT so  You often want to parse a word during compilation and compile its XT so
Line 2892  this: Line 2894  this:
 : foo 100 throw ;  : foo 100 throw ;
 : foo1 foo ." after foo" ;  : foo1 foo ." after foo" ;
 : bar ['] foo1 catch ;  : bar ['] foo1 catch ;
 bar  bar .
 @end example  @end example
   
 It is often important to restore a value upon leaving a definition, even  It is often important to restore a value upon leaving a definition, even
Line 3015  Definition and use of field offsets now Line 3017  Definition and use of field offsets now
   
 @example  @example
 2 cells simple-field field1  2 cells simple-field field1
 ( addr ) field1  create mystruct 4 cells allot
   mystruct .s field1 .s drop
 @end example  @end example
   
 If you want to do something with the word without performing the code  If you want to do something with the word without performing the code
Line 3149  Instead, you can use @code{LITERAL (comp Line 3152  Instead, you can use @code{LITERAL (comp
 : [FOO] ( compilation: --; run-time: -- n )  : [FOO] ( compilation: --; run-time: -- n )
   500 POSTPONE literal ; immediate    500 POSTPONE literal ; immediate
   
 : flip foo ;  : flip [FOO] ;
 flip .  flip .
 see flip  see flip
 @end example  @end example
Line 3266  interpretation semantics: Line 3269  interpretation semantics:
   
 @example  @example
 ' if  ' if
 comp' if .s  comp' if .s 2drop
 @end example  @end example
   
   
Removed from v.1.59  
changed lines
  Added in v.1.60

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