--- gforth/search.fs 1998/05/02 21:28:43 1.4 +++ gforth/search.fs 2003/01/19 23:35:30 1.21 @@ -1,6 +1,6 @@ \ search order wordset 14may93py -\ Copyright (C) 1995 Free Software Foundation, Inc. +\ Copyright (C) 1995-2003 Free Software Foundation, Inc. \ This file is part of Gforth. @@ -16,19 +16,30 @@ \ 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. +\ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA. -$10 constant maxvp -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 ! ; - -\ : context ( -- addr ) vp dup @ cells + ; -: vp! dup vp ! cells vp + to context ; -: definitions ( -- ) context @ current ! ; +$10 Value maxvp \ current size of search order stack +$400 Value maxvp-limit \ upper limit for resizing search order stack +0 AValue vp \ will be initialized later (dynamic) + +: get-current ( -- wid ) \ search + \G @i{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 @i{wid}. + current ! ; + +:noname ( -- addr ) + vp dup @ cells + ; +is context + +: vp! ( u -- ) + vp ! ; +: definitions ( -- ) \ search + \G Set the compilation word list to be the same as the word list + \G that is currently at the top of the search order. + context @ current ! ; \ wordlist Vocabulary also previous 14may93py @@ -37,12 +48,13 @@ 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 @i{wid}. slowvoc @ IF \ this is now f83search because hashing may be loaded already \ jaw @@ -50,13 +62,33 @@ 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 replace the @i{wid} at the + \G top of the search order with the @i{wid} associated with the new + \G word list. + Create wordlist drop DOES> context ! ; + +: check-maxvp ( n -- ) + dup maxvp-limit > -49 and throw + dup maxvp > IF + BEGIN dup maxvp 2* dup TO maxvp <= UNTIL + vp maxvp 1+ cells resize throw TO vp + THEN drop ; + +: >order ( wid -- ) \ gforth to-order + \g Push @var{wid} on the search order. + vp @ 1+ dup check-maxvp vp! context ! ; + +: also ( -- ) \ search-ext + \G Like @code{DUP} for the search order. Usually used before a + \G vocabulary (e.g., @code{also Forth}); the combined effect is to push + \G the wordlist represented by the vocabulary on the search order. + context @ >order ; + +: previous ( -- ) \ search-ext + \G Drop the wordlist at the top of the search order. + vp @ 1- dup 0= -50 and throw vp! ; \ vocabulary find 14may93py @@ -102,17 +134,36 @@ slowvoc off \ Only root 14may93py -Vocabulary Forth -Vocabulary Root +Vocabulary Forth ( -- ) \ gforthman- search-ext + \G Replace the @i{wid} at the top of the search order with the + \G @i{wid} associated with the word list @code{forth-wordlist}. + + +Vocabulary Root ( -- ) \ gforth + \G Add the root wordlist to the search order stack. This vocabulary + \G makes up the minimum search order and contains only a + \G search-order 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 ; + +: init-vp ( -- ) + $10 TO maxvp + maxvp 1+ cells allocate throw TO vp + Only Forth also definitions ; + +:noname + init-vp DEFERS 'cold ; +IS 'cold -: Only 1 vp! Root also ; +init-vp \ 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 lookup ! \ our dictionary search order becomes the law ( -- ) ' Forth >body to Forth-wordlist \ "forth definitions get-current" and "forth-wordlist" should produce the same wid @@ -120,24 +171,45 @@ lookup ! \ our dictionary search order b \ get-order set-order 14may93py -: get-order ( -- wid1 .. widn n ) - 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 ; +: get-order ( -- widn .. wid1 n ) \ search + \G Copy the search order to the data stack. The current search order + \G has @i{n} entries, of which @i{wid1} represents the wordlist + \G that is searched first (the word list at the top of the search + \G order) and @i{widn} represents the wordlist that is searched + \G last. + vp @ 0 ?DO vp cell+ I cells + @ LOOP vp @ ; + +: set-order ( widn .. wid1 n -- ) \ gforthman- 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 name>string type space ; + body> >head-noprim 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 ( -- ) \ gforthman- 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 +217,7 @@ 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 +228,14 @@ 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 @code{Constant} -- @i{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 search order. ' set-order alias set-order ' order alias order