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Diff for /gforth/doc/gforth.ds between versions 1.35 and 1.36

version 1.35, 1999/05/21 20:35:37 version 1.36, 1999/05/22 20:03:54
Line 8 Line 8
 @comment 4. search for TODO for other minor and major works required.  @comment 4. search for TODO for other minor and major works required.
 @comment 5. [rats] change all @var to @i in Forth source so that info  @comment 5. [rats] change all @var to @i in Forth source so that info
 @comment    file looks decent.  @comment    file looks decent.
   @c          Not an improvement IMO - anton
   @c          and anyway, this should be taken up
   @c          with Karl Berry (the texinfo guy) - anton
 @comment .. would be useful to have a word that identified all deferred words  @comment .. would be useful to have a word that identified all deferred words
 @comment should semantics stuff in intro be moved to another section  @comment should semantics stuff in intro be moved to another section
   
Line 5129  execution token. You can produce the exe Line 5132  execution token. You can produce the exe
   
 @example  @example
 : greet ( -- )   ." Hello" ;  : greet ( -- )   ." Hello" ;
 : foo ( -- xt )  ['] greet ; \ ['] parses greet at compile-time  : foo ( -- xt )  ['] greet execute ; \ ['] parses greet at compile-time
 : bar ( -- )     ' EXECUTE ; \  '  parses at run-time  : bar ( -- )     ' execute ; \  '  parses at run-time
   
 \ the next four lines all do the same thing  \ the next four lines all do the same thing
 foo EXECUTE  foo
   bar greet
 greet  greet
 ' greet EXECUTE  ' greet EXECUTE
 boo greet  
 @end example  @end example
   
 An execution token occupies one cell.  An execution token occupies one cell.
Line 5166  At present, the @i{w} part of a compilat Line 5169  At present, the @i{w} part of a compilat
 and the @i{xt} part represents either @code{execute} or  and the @i{xt} part represents either @code{execute} or
 @code{compile,}@footnote{Depending upon the compilation semantics of the  @code{compile,}@footnote{Depending upon the compilation semantics of the
 word. If the word has default compilation semantics, the @i{xt} will  word. If the word has default compilation semantics, the @i{xt} will
 represent @code{compile,}. If the word is @code{immediate}, the @i{xt}  represent @code{compile,}. Otherwise (e.g., for immediate words), the
 will represent @code{execute}.}. However, don't rely on that knowledge,  @i{xt} will represent @code{execute}.}. However, don't rely on that
 unless necessary; future versions of Gforth may introduce unusual  knowledge, unless necessary; future versions of Gforth may introduce
 compilation tokens (e.g., a compilation token that represents the  unusual compilation tokens (e.g., a compilation token that represents
 compilation semantics of a literal).  the compilation semantics of a literal).
   
 You can compile the compilation semantics with @code{postpone,}. I.e.,  You can compile the compilation semantics with @code{postpone,}. I.e.,
 @code{COMP' @i{word} postpone,} is equivalent to @code{postpone  @code{COMP' @i{word} postpone,} is equivalent to @code{postpone
Line 5203  doc-name>string Line 5206  doc-name>string
 @cindex word lists  @cindex word lists
 @cindex header space  @cindex header space
   
 @cindex wid  A wordlist is a list of named words; you can add new words and look up
 All definitions other than those created by @code{:noname} have an entry  words by name (and you can remove words in a restricted way with
 in the header space. The header space is fragmented into a number  markers).  Every named (and @code{reveal}ed) word is in one wordlist.
 of parts, called @dfn{word lists}. A word list is identified by a  
 cell-sized word list identifier (@i{wid}) in much the same way as a  @cindex search order stack
 file is identified by a file handle. The numerical value of the wid has  The text interpreter searches the wordlists present in the search order
 no (portable) meaning, and might change from session to session.  (a stack of wordlists), from the top to the bottom.  Within each
   wordlist, the search starts conceptually at the newest word; i.e., if
   two words in a wordlist have the same name, the newer word is found.
   
 @cindex compilation word list  @cindex compilation word list
 At any one time, a single word list is defined as the word list to which  New words are added to the @dfn{compilation wordlist} (aka current
 all new definitions will be added -- this is called the @dfn{compilation  wordlist).
 word list}. When Gforth is started, the compilation word list is the  
 word list called @code{FORTH-WORDLIST}.  
   
 @cindex search order stack  @cindex wid
 Forth maintains a stack of word lists, representing the @dfn{search  A word list is identified by a cell-sized word list identifier (@i{wid})
 order}.  When the header space is searched (for example, when  in much the same way as a file is identified by a file handle. The
 attempting to find a word's execution token during compilation), only  numerical value of the wid has no (portable) meaning, and might change
 those word lists that are currently in the search order are  from session to session.
 searched. The most recently-defined word in the word list at the top of  
 the word list stack is searched first, and the search proceeds until  
 either the word is located or the oldest definition in the word list at  
 the bottom of the stack is reached. Definitions of the word may exist in  
 more than one word lists; the search order determines which version will  
 be found.  
   
 The ANS Forth ``Search order'' word set is intended to provide a set of  The ANS Forth ``Search order'' word set is intended to provide a set of
 low-level tools that allow various different schemes to be  low-level tools that allow various different schemes to be
Line 5248  doc-get-order Line 5245  doc-get-order
 doc---thisone-set-order  doc---thisone-set-order
 doc-wordlist  doc-wordlist
 doc-table  doc-table
   doc-push-order
   doc-previous
 doc-also  doc-also
 doc---thisone-forth  doc---thisone-forth
 doc-only  doc-only
 doc---thisone-order  doc---thisone-order
 doc-previous  
   
 doc-find  doc-find
 doc-search-wordlist  doc-search-wordlist
Removed from v.1.35  
changed lines
  Added in v.1.36

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