Annotation of gforth/search.fs, revision 1.11
1.1 anton 1: \ search order wordset 14may93py
2:
1.6 anton 3: \ Copyright (C) 1995,1996,1997,1998 Free Software Foundation, Inc.
1.1 anton 4:
5: \ This file is part of Gforth.
6:
7: \ Gforth is free software; you can redistribute it and/or
8: \ modify it under the terms of the GNU General Public License
9: \ as published by the Free Software Foundation; either version 2
10: \ of the License, or (at your option) any later version.
11:
12: \ This program is distributed in the hope that it will be useful,
13: \ but WITHOUT ANY WARRANTY; without even the implied warranty of
14: \ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15: \ GNU General Public License for more details.
16:
17: \ You should have received a copy of the GNU General Public License
18: \ along with this program; if not, write to the Free Software
19: \ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20:
21: $10 constant maxvp
22: Variable vp
23: 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A,
24: 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A,
25:
1.7 crook 26: : get-current ( -- wid ) \ search
1.8 crook 27: \G @var{wid} is the identifier of the current compilation word list.
1.7 crook 28: current @ ;
29:
30: : set-current ( wid -- ) \ search
1.8 crook 31: \G Set the compilation word list to the word list identified by @var{wid}.
1.7 crook 32: current ! ;
1.1 anton 33:
1.11 ! anton 34: :noname ( -- addr )
! 35: vp dup @ cells + ;
! 36: is context
! 37:
! 38: : vp! ( u -- )
! 39: vp ! ;
1.7 crook 40: : definitions ( -- ) \ search
41: \G Make the compilation word list the same as the word list
42: \G that is currently at the top of the search order stack.
43: context @ current ! ;
1.1 anton 44:
45: \ wordlist Vocabulary also previous 14may93py
46:
1.2 jwilke 47: Variable slowvoc 0 slowvoc !
1.1 anton 48:
1.2 jwilke 49: \ Forth-wordlist AConstant Forth-wordlist
1.1 anton 50:
1.2 jwilke 51: : mappedwordlist ( map-struct -- wid ) \ gforth
1.7 crook 52: \G Create a wordlist with a special map-structure.
1.5 pazsan 53: here swap A, 0 A, voclink @ A, 0 A,
1.2 jwilke 54: dup wordlist-link voclink !
55: dup initvoc ;
1.1 anton 56:
1.7 crook 57: : wordlist ( -- wid ) \ search
1.8 crook 58: \G Create a new, empty word list represented by @var{wid}.
1.1 anton 59: slowvoc @
1.2 jwilke 60: IF \ this is now f83search because hashing may be loaded already
61: \ jaw
62: f83search
1.1 anton 63: ELSE Forth-wordlist wordlist-map @ THEN
1.2 jwilke 64: mappedwordlist ;
1.1 anton 65:
1.7 crook 66: : Vocabulary ( "name" -- ) \ gforth
67: \G Create a definition "name" and associate a new word list with it.
68: \G The run-time effect of "name" is to push the new word list's wid
69: \G onto the top of the search order stack.
70: Create wordlist drop DOES> context ! ;
71:
1.10 anton 72: : check-maxvp ( n -- )
73: maxvp > -49 and throw ;
74:
75: : push-order ( wid -- ) \ gforth
76: \g Push @var{wid} on the search order.
77: vp @ 1+ dup check-maxvp vp! context ! ;
78:
1.7 crook 79: : also ( -- ) \ search ext
1.8 crook 80: \G Perform a @code{DUP} on the search order stack. Usually used prior
1.7 crook 81: \G to @code{Forth}, @code{definitions} etc.
1.10 anton 82: context @ push-order ;
1.1 anton 83:
1.7 crook 84: : previous ( -- ) \ search ext
1.11 ! anton 85: \G Perform a @code{DROP} on the search order stack, thereby removing
! 86: \G the wid at the top of the (search order) stack from the search
! 87: \G order.
1.10 anton 88: vp @ 1- dup 0= -50 and throw vp! ;
1.1 anton 89:
90: \ vocabulary find 14may93py
91:
92: : (vocfind) ( addr count wid -- nfa|false )
93: \ !! generalize this to be independent of vp
94: drop vp dup @ 1- cells over +
95: DO 2dup I 2@ over <>
96: IF (search-wordlist) dup
97: IF nip nip UNLOOP EXIT
98: THEN drop
99: ELSE drop 2drop THEN
100: [ -1 cells ] Literal +LOOP
101: 2drop false ;
102:
103: 0 value locals-wordlist
104:
105: : (localsvocfind) ( addr count wid -- nfa|false )
106: \ !! use generalized (vocfind)
107: drop locals-wordlist
108: IF 2dup locals-wordlist (search-wordlist) dup
109: IF nip nip
110: EXIT
111: THEN drop
112: THEN
113: 0 (vocfind) ;
114:
115: \ In the kernel the dictionary search works on only one wordlist.
116: \ The following stuff builds a thing that looks to the kernel like one
117: \ wordlist, but when searched it searches the whole search order
118: \ (including locals)
119:
120: \ this is the wordlist-map of the dictionary
121: Create vocsearch ( -- wordlist-map )
1.2 jwilke 122: ' (localsvocfind) A, ' (reveal) A, ' drop A, ' drop A,
123:
124: \ create dummy wordlist for kernel
125: slowvoc on
126: vocsearch mappedwordlist \ the wordlist structure ( -- wid )
127:
128: \ we don't want the dummy wordlist in our linked list
129: 0 Voclink !
130: slowvoc off
1.1 anton 131:
132: \ Only root 14may93py
133:
1.9 crook 134: Vocabulary Forth ( -- ) \ thisone- search-ext
135: \G Push the @var{wid} associated with @code{forth-wordlist} onto the
136: \G search order stack.
137:
1.7 crook 138: Vocabulary Root ( -- ) \ gforth
139: \G Add the vocabulary @code{Root} to the search order stack.
140: \G This vocabulary makes up the minimum search order and
141: \G contains these words: @code{order} @code{set-order}
142: \G @code{forth-wordlist} @code{Forth} @code{words}
143:
1.9 crook 144: : Only ( -- ) \ search-ext
1.7 crook 145: \G Set the search order to the implementation-defined minimum search
1.8 crook 146: \G order (for Gforth, this is the word list @code{Root}).
1.7 crook 147: 1 vp! Root also ;
1.1 anton 148:
149: \ set initial search order 14may93py
150:
1.5 pazsan 151: Forth-wordlist wordlist-id @ ' Forth >body wordlist-id !
1.1 anton 152:
1.2 jwilke 153: 0 vp! also Root also definitions
1.1 anton 154: Only Forth also definitions
1.2 jwilke 155: lookup ! \ our dictionary search order becomes the law ( -- )
1.1 anton 156:
157: ' Forth >body to Forth-wordlist \ "forth definitions get-current" and "forth-wordlist" should produce the same wid
158:
159:
160: \ get-order set-order 14may93py
161:
1.7 crook 162: : get-order ( -- widn .. wid1 n ) \ search
163: \G Copy the search order stack to the data stack. The current search
1.8 crook 164: \G order has @var{n} entries, of which @var{wid1} represents the word
1.7 crook 165: \G list that is searched first (the word list at the top of the stack) and
1.8 crook 166: \G @var{widn} represents the word order that is searched last.
1.1 anton 167: vp @ 0 ?DO vp cell+ I cells + @ LOOP vp @ ;
168:
1.9 crook 169: : set-order ( widn .. wid1 n -- ) \ thisone- search
1.10 anton 170: \G If @var{n}=0, empty the search order. If @var{n}=-1, set the
171: \G search order to the implementation-defined minimum search order
172: \G (for Gforth, this is the word list @code{Root}). Otherwise,
173: \G replace the existing search order with the @var{n} wid entries
174: \G such that @var{wid1} represents the word list that will be
175: \G searched first and @var{widn} represents the word list that will
176: \G be searched last.
177: dup -1 = IF
178: drop only exit
179: THEN
180: dup check-maxvp
181: dup vp!
182: ?dup IF 1- FOR vp cell+ I cells + ! NEXT THEN ;
1.1 anton 183:
1.7 crook 184: : seal ( -- ) \ gforth
185: \G Remove all word lists from the search order stack other than the word
186: \G list that is currently on the top of the search order stack.
187: context @ 1 set-order ;
1.1 anton 188:
1.2 jwilke 189: : .voc
1.4 pazsan 190: body> >head name>string type space ;
1.1 anton 191:
1.9 crook 192: : order ( -- ) \ thisone- search-ext
193: \G Print the search order and the compilation word list. The
194: \G word lists are printed in the order in which they are searched
195: \G (which is reversed with respect to the conventional way of
196: \G displaying stacks). The compilation word list is displayed last.
197: \ The standard requires that the word lists are printed in the order
198: \ in which they are searched. Therefore, the output is reversed
199: \ with respect to the conventional way of displaying stacks.
1.1 anton 200: get-order 0
201: ?DO
202: .voc
203: LOOP
204: 4 spaces get-current .voc ;
1.2 jwilke 205:
1.1 anton 206: : vocs ( -- ) \ gforth
1.7 crook 207: \G List vocabularies and wordlists defined in the system.
1.1 anton 208: voclink
209: BEGIN
1.2 jwilke 210: @ dup
1.1 anton 211: WHILE
212: dup 0 wordlist-link - .voc
213: REPEAT
214: drop ;
215:
216: Root definitions
217:
1.9 crook 218: ' words Alias words ( -- ) \ tools
219: \G Display a list of all of the definitions in the word list at the top
220: \G of the search order.
221: ' Forth Alias Forth
1.7 crook 222: ' forth-wordlist alias forth-wordlist ( -- wid ) \ search
1.8 crook 223: \G CONSTANT: @var{wid} identifies the word list that includes all of the standard words
1.7 crook 224: \G provided by Gforth. When Gforth is invoked, this word list is the compilation word
225: \G list and is at the top of the word list stack.
1.9 crook 226: ' set-order alias set-order
227: ' order alias order
1.1 anton 228:
229: Forth definitions
230:
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