Annotation of gforth/kernel/toolsext.fs, revision 1.30
1.30 ! anton 1: \ Copyright (C) 1995,1998,2000,2003,2005,2007,2009,2010,2012 Free Software Foundation, Inc.
1.1 anton 2:
3: \ This file is part of Gforth.
4:
5: \ Gforth is free software; you can redistribute it and/or
6: \ modify it under the terms of the GNU General Public License
1.22 anton 7: \ as published by the Free Software Foundation, either version 3
1.1 anton 8: \ of the License, or (at your option) any later version.
9:
10: \ This program is distributed in the hope that it will be useful,
11: \ but WITHOUT ANY WARRANTY; without even the implied warranty of
12: \ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13: \ GNU General Public License for more details.
14:
15: \ You should have received a copy of the GNU General Public License
1.22 anton 16: \ along with this program. If not, see http://www.gnu.org/licenses/.
1.1 anton 17:
1.3 jwilke 18: Warnings off
1.1 anton 19:
20: Variable countif
21:
22: : dummy ; immediate
23: : >exec >r ; restrict ( :-)
1.10 anton 24: : scanIF f83find dup 0= IF drop ['] dummy >head-noprim THEN ;
1.1 anton 25:
1.2 jwilke 26: Create [struct]-search ' scanIF A, ' (reveal) A, ' drop A, ' drop A,
1.5 pazsan 27: Create [struct]-voc [struct]-search A,
28: NIL A, NIL A, NIL A,
1.1 anton 29:
30: : ?if countif @ 0<
31: IF [ [struct]-voc 3 cells + ] ALiteral @ lookup ! THEN ;
32:
33: UNLOCK Tlast @ TNIL Tlast ! LOCK
34: \ last @ 0 last !
35:
1.8 crook 36: : [IF]
37: 1 countif +! ?if ; immediate
38: : [THEN]
39: -1 countif +! ?if ; immediate
40: : [ELSE]
1.26 anton 41: postpone [THEN] postpone [IF] ; immediate
42:
1.1 anton 43: ' [IF] Alias [IFDEF] immediate
44: ' [IF] Alias [IFUNDEF] immediate
1.8 crook 45: ' [THEN] Alias [ENDIF] immediate
1.1 anton 46: ' [IF] Alias [BEGIN] immediate
47: ' [IF] Alias [WHILE] immediate
48: ' [THEN] Alias [UNTIL] immediate
49: ' [THEN] Alias [AGAIN] immediate
50: ' [IF] Alias [DO] immediate
51: ' [IF] Alias [?DO] immediate
52: ' [THEN] Alias [LOOP] immediate
53: ' [THEN] Alias [+LOOP] immediate
54: : [REPEAT] postpone [AGAIN] postpone [THEN] ;
55: immediate
1.17 anton 56: \ The following was too smart for its own good; consider "postpone (".
57: \ Moreover, ANS Forth specifies that the next [THEN] ends an [IF]
58: \ (even if its in a '( ... )').
59:
60: \ ' ( Alias ( immediate ( keep fontify happy)
61: \ ' \ Alias \ immediate
1.1 anton 62:
63: UNLOCK Tlast @ swap Tlast ! LOCK
64: \ last @ swap last !
1.5 pazsan 65: 1 cells - [struct]-voc cell+ !
1.1 anton 66:
67: \ Interpretative Structuren 30apr92py
68:
1.27 anton 69: : [defined] ( "<spaces>name" -- flag ) parse-name find-name 0<> ; immediate
1.13 pazsan 70: \G returns true if name is found in current search order
1.14 anton 71: ' [defined] alias defined immediate
1.13 pazsan 72: : [undefined] ( "<spaces>name" -- flag ) postpone [defined] 0= ; immediate
73: \G returns false if name is found in current search order
1.8 crook 74:
1.13 pazsan 75: : [IF] ( flag -- ) \ tools-ext bracket-if
1.8 crook 76: \G If flag is @code{TRUE} do nothing (and therefore
77: \G execute subsequent words as normal). If flag is @code{FALSE},
78: \G parse and discard words from the parse
79: \G area (refilling it if necessary using
80: \G @code{REFILL}) including nested instances of @code{[IF]}..
81: \G @code{[ELSE]}.. @code{[THEN]} and @code{[IF]}.. @code{[THEN]}
82: \G until the balancing @code{[ELSE]} or @code{[THEN]} has been
83: \G parsed and discarded. Immediate word.
84: 0= IF countif off
1.1 anton 85: lookup @ [ [struct]-voc 3 cells + ] ALiteral !
86: [struct]-voc lookup !
87: THEN ; immediate
1.8 crook 88:
89: : [IFDEF] ( "<spaces>name" -- ) \ gforth bracket-if-def
90: \G If name is found in the current search-order, behave like
1.9 crook 91: \G @code{[IF]} with a @code{TRUE} flag, otherwise behave like
1.8 crook 92: \G @code{[IF]} with a @code{FALSE} flag. Immediate word.
1.13 pazsan 93: postpone [defined] postpone [IF] ; immediate
1.8 crook 94:
95: : [IFUNDEF] ( "<spaces>name" -- ) \ gforth bracket-if-un-def
96: \G If name is not found in the current search-order, behave like
1.9 crook 97: \G @code{[IF]} with a @code{TRUE} flag, otherwise behave like
1.8 crook 98: \G @code{[IF]} with a @code{FALSE} flag. Immediate word.
1.13 pazsan 99: postpone [defined] 0= postpone [IF] ; immediate
1.8 crook 100:
1.13 pazsan 101: : [ELSE] ( -- ) \ tools-ext bracket-else
1.8 crook 102: \G Parse and discard words from the parse
103: \G area (refilling it if necessary using
104: \G @code{REFILL}) including nested instances of @code{[IF]}..
105: \G @code{[ELSE]}.. @code{[THEN]} and @code{[IF]}.. @code{[THEN]}
106: \G until the balancing @code{[THEN]} has been parsed and discarded.
107: \G @code{[ELSE]} only gets executed if the balancing @code{[IF]}
108: \G was @code{TRUE}; if it was @code{FALSE}, @code{[IF]} would
109: \G have parsed and discarded the @code{[ELSE]}, leaving the
110: \G subsequent words to be executed as normal.
111: \G Immediate word.
112: 0 postpone [IF] ; immediate
113:
114: : [THEN] ( -- ) \ tools-ext bracket-then
115: \G Do nothing; used as a marker for other words to parse
1.9 crook 116: \G and discard up to. Immediate word.
1.8 crook 117: ; immediate
118:
119: : [ENDIF] ( -- ) \ gforth bracket-end-if
1.9 crook 120: \G Do nothing; synonym for @code{[THEN]}
1.8 crook 121: ; immediate
1.1 anton 122:
123: \ Structs for interpreter 28nov92py
124:
125: User (i)
126:
1.8 crook 127: : [DO] ( n-limit n-index -- ) \ gforth bracket-do
128: >in @ -rot
1.1 anton 129: DO I (i) ! dup >r >in ! interpret r> swap +LOOP drop ;
130: immediate
1.8 crook 131:
132: : [?DO] ( n-limit n-index -- ) \ gforth bracket-question-do
133: 2dup = IF 2drop postpone [ELSE] ELSE postpone [DO] THEN ;
1.1 anton 134: immediate
1.8 crook 135:
136: : [+LOOP] ( n -- ) \ gforth bracket-question-plus-loop
1.29 pazsan 137: rdrop lp+ ; immediate
1.8 crook 138:
139: : [LOOP] ( -- ) \ gforth bracket-loop
1.29 pazsan 140: 1 rdrop lp+ ; immediate
1.8 crook 141:
142: : [FOR] ( n -- ) \ gforth bracket-for
143: 0 swap postpone [DO] ; immediate
144:
145: : [NEXT] ( n -- ) \ gforth bracket-next
1.29 pazsan 146: -1 rdrop lp+ ; immediate
1.8 crook 147:
1.4 pazsan 148: :noname (i) @ ;
149: :noname (i) @ postpone Literal ;
1.8 crook 150: interpret/compile: [I] ( -- n ) \ gforth bracket-i
151:
152: : [BEGIN] ( -- ) \ gforth bracket-begin
1.29 pazsan 153: >in @ >r BEGIN r@ >in ! interpret UNTIL rdrop lp+ ; immediate
1.8 crook 154:
155: ' [+LOOP] Alias [UNTIL] ( flag -- ) \ gforth bracket-until
1.1 anton 156: immediate
1.8 crook 157:
158: : [REPEAT] ( -- ) \ gforth bracket-repeat
1.29 pazsan 159: false rdrop lp+ ; immediate
1.8 crook 160:
161: ' [REPEAT] Alias [AGAIN] ( -- ) \ gforth bracket-again
162: immediate
163:
164: : [WHILE] ( flag -- ) \ gforth bracket-while
1.29 pazsan 165: 0= IF postpone [ELSE] true rdrop lp+ 1 countif +! THEN ;
1.1 anton 166: immediate
167:
1.24 pazsan 168: \ Warnings on
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