--- gforth/search.fs 1997/07/06 15:55:25 1.2 +++ gforth/search.fs 1999/05/22 20:03:53 1.10 @@ -1,6 +1,6 @@ \ search order wordset 14may93py -\ Copyright (C) 1995 Free Software Foundation, Inc. +\ Copyright (C) 1995,1996,1997,1998 Free Software Foundation, Inc. \ This file is part of Gforth. @@ -23,12 +23,20 @@ Variable vp 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, -: get-current ( -- wid ) current @ ; -: set-current ( wid -- ) current ! ; +: get-current ( -- wid ) \ search + \G @var{wid} is the identifier of the current compilation word list. + current @ ; + +: set-current ( wid -- ) \ search + \G Set the compilation word list to the word list identified by @var{wid}. + current ! ; \ : context ( -- addr ) vp dup @ cells + ; : vp! dup vp ! cells vp + to context ; -: definitions ( -- ) context @ current ! ; +: definitions ( -- ) \ search + \G Make the compilation word list the same as the word list + \G that is currently at the top of the search order stack. + context @ current ! ; \ wordlist Vocabulary also previous 14may93py @@ -37,12 +45,13 @@ Variable slowvoc 0 slowvoc ! \ Forth-wordlist AConstant Forth-wordlist : mappedwordlist ( map-struct -- wid ) \ gforth -\G creates a wordlist with a special map-structure - here 0 A, swap A, voclink @ A, 0 A, +\G Create a wordlist with a special map-structure. + here swap A, 0 A, voclink @ A, 0 A, dup wordlist-link voclink ! dup initvoc ; -: wordlist ( -- wid ) +: wordlist ( -- wid ) \ search + \G Create a new, empty word list represented by @var{wid}. slowvoc @ IF \ this is now f83search because hashing may be loaded already \ jaw @@ -50,13 +59,28 @@ Variable slowvoc 0 slowvoc ! ELSE Forth-wordlist wordlist-map @ THEN mappedwordlist ; -: Vocabulary ( -- ) Create wordlist drop DOES> context ! ; - -: also ( -- ) - context @ vp @ 1+ dup maxvp > abort" Vocstack full" - vp! context ! ; - -: previous ( -- ) vp @ 1- dup 0= abort" Vocstack empty" vp! ; +: Vocabulary ( "name" -- ) \ gforth + \G Create a definition "name" and associate a new word list with it. + \G The run-time effect of "name" is to push the new word list's wid + \G onto the top of the search order stack. + Create wordlist drop DOES> context ! ; + +: check-maxvp ( n -- ) + maxvp > -49 and throw ; + +: push-order ( wid -- ) \ gforth + \g Push @var{wid} on the search order. + vp @ 1+ dup check-maxvp vp! context ! ; + +: also ( -- ) \ search ext + \G Perform a @code{DUP} on the search order stack. Usually used prior + \G to @code{Forth}, @code{definitions} etc. + context @ push-order ; + +: previous ( -- ) \ search ext + \G Perform a @code{DROP} on the search order stack, thereby removing the wid at the + \G top of the (search order) stack from the search order. + vp @ 1- dup 0= -50 and throw vp! ; \ vocabulary find 14may93py @@ -102,14 +126,24 @@ slowvoc off \ Only root 14may93py -Vocabulary Forth -Vocabulary Root - -: Only 0 vp! also Root also definitions ; +Vocabulary Forth ( -- ) \ thisone- search-ext + \G Push the @var{wid} associated with @code{forth-wordlist} onto the + \G search order stack. + +Vocabulary Root ( -- ) \ gforth + \G Add the vocabulary @code{Root} to the search order stack. + \G This vocabulary makes up the minimum search order and + \G contains these words: @code{order} @code{set-order} + \G @code{forth-wordlist} @code{Forth} @code{words} + +: Only ( -- ) \ search-ext + \G Set the search order to the implementation-defined minimum search + \G order (for Gforth, this is the word list @code{Root}). + 1 vp! Root also ; \ set initial search order 14may93py -Forth-wordlist @ ' Forth >body ! +Forth-wordlist wordlist-id @ ' Forth >body wordlist-id ! 0 vp! also Root also definitions Only Forth also definitions @@ -120,24 +154,44 @@ lookup ! \ our dictionary search order b \ get-order set-order 14may93py -: get-order ( -- wid1 .. widn n ) +: get-order ( -- widn .. wid1 n ) \ search + \G Copy the search order stack to the data stack. The current search + \G order has @var{n} entries, of which @var{wid1} represents the word + \G list that is searched first (the word list at the top of the stack) and + \G @var{widn} represents the word order that is searched last. vp @ 0 ?DO vp cell+ I cells + @ LOOP vp @ ; -: set-order ( wid1 .. widn n / -1 -- ) - dup -1 = IF drop Only exit THEN dup vp! - ?dup IF 1- FOR vp cell+ I cells + ! NEXT THEN ; - -: seal ( -- ) context @ 1 set-order ; +: set-order ( widn .. wid1 n -- ) \ thisone- search + \G If @var{n}=0, empty the search order. If @var{n}=-1, set the + \G search order to the implementation-defined minimum search order + \G (for Gforth, this is the word list @code{Root}). Otherwise, + \G replace the existing search order with the @var{n} wid entries + \G such that @var{wid1} represents the word list that will be + \G searched first and @var{widn} represents the word list that will + \G be searched last. + dup -1 = IF + drop only exit + THEN + dup check-maxvp + dup vp! + ?dup IF 1- FOR vp cell+ I cells + ! NEXT THEN ; + +: seal ( -- ) \ gforth + \G Remove all word lists from the search order stack other than the word + \G list that is currently on the top of the search order stack. + context @ 1 set-order ; : .voc - body> >head head>string type space ; + body> >head name>string type space ; -: order ( -- ) \ search-ext - \g prints the search order and the @code{current} wordlist. The - \g standard requires that the wordlists are printed in the order - \g in which they are searched. Therefore, the output is reversed - \g with respect to the conventional way of displaying stacks. The - \g @code{current} wordlist is displayed last. +: order ( -- ) \ thisone- search-ext + \G Print the search order and the compilation word list. The + \G word lists are printed in the order in which they are searched + \G (which is reversed with respect to the conventional way of + \G displaying stacks). The compilation word list is displayed last. + \ The standard requires that the word lists are printed in the order + \ in which they are searched. Therefore, the output is reversed + \ with respect to the conventional way of displaying stacks. get-order 0 ?DO .voc @@ -145,7 +199,7 @@ lookup ! \ our dictionary search order b 4 spaces get-current .voc ; : vocs ( -- ) \ gforth - \g prints vocabularies and wordlists defined in the system. + \G List vocabularies and wordlists defined in the system. voclink BEGIN @ dup @@ -156,9 +210,14 @@ lookup ! \ our dictionary search order b Root definitions -' words Alias words +' words Alias words ( -- ) \ tools +\G Display a list of all of the definitions in the word list at the top +\G of the search order. ' Forth Alias Forth -' forth-wordlist alias forth-wordlist +' forth-wordlist alias forth-wordlist ( -- wid ) \ search + \G CONSTANT: @var{wid} identifies the word list that includes all of the standard words + \G provided by Gforth. When Gforth is invoked, this word list is the compilation word + \G list and is at the top of the word list stack. ' set-order alias set-order ' order alias order