Annotation of gforth/glocals.fs, revision 1.35
1.15 anton 1: \ A powerful locals implementation
2:
3: \ Copyright (C) 1995 Free Software Foundation, Inc.
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:
1.16 anton 22: \ More documentation can be found in the manual and in
23: \ http://www.complang.tuwien.ac.at/papers/ertl94l.ps.gz
24:
1.1 anton 25: \ Local variables are quite important for writing readable programs, but
26: \ IMO (anton) they are the worst part of the standard. There they are very
27: \ restricted and have an ugly interface.
28:
29: \ So, we implement the locals wordset, but do not recommend using
30: \ locals-ext (which is a really bad user interface for locals).
31:
32: \ We also have a nice and powerful user-interface for locals: locals are
33: \ defined with
34:
35: \ { local1 local2 ... }
36: \ or
37: \ { local1 local2 ... -- ... }
38: \ (anything after the -- is just a comment)
39:
40: \ Every local in this list consists of an optional type specification
41: \ and a name. If there is only the name, it stands for a cell-sized
42: \ value (i.e., you get the value of the local variable, not it's
43: \ address). The following type specifiers stand before the name:
44:
45: \ Specifier Type Access
46: \ W: Cell value
47: \ W^ Cell address
48: \ D: Double value
49: \ D^ Double address
50: \ F: Float value
51: \ F^ Float address
52: \ C: Char value
53: \ C^ Char address
54:
55: \ The local variables are initialized with values from the appropriate
56: \ stack. In contrast to the examples in the standard document our locals
57: \ take the arguments in the expected way: The last local gets the top of
58: \ stack, the second last gets the second stack item etc. An example:
59:
60: \ : CX* { F: Ar F: Ai F: Br F: Bi -- Cr Ci }
61: \ \ complex multiplication
62: \ Ar Br f* Ai Bi f* f-
63: \ Ar Bi f* Ai Br f* f+ ;
64:
65: \ There will also be a way to add user types, but it is not yet decided,
66: \ how. Ideas are welcome.
67:
68: \ Locals defined in this manner live until (!! see below).
69: \ Their names can be used during this time to get
70: \ their value or address; The addresses produced in this way become
71: \ invalid at the end of the lifetime.
72:
73: \ Values can be changed with TO, but this is not recomended (TO is a
74: \ kludge and words lose the single-assignment property, which makes them
75: \ harder to analyse).
76:
77: \ As for the internals, we use a special locals stack. This eliminates
78: \ the problems and restrictions of reusing the return stack and allows
79: \ to store floats as locals: the return stack is not guaranteed to be
80: \ aligned correctly, but our locals stack must be float-aligned between
81: \ words.
82:
83: \ Other things about the internals are pretty unclear now.
84:
85: \ Currently locals may only be
86: \ defined at the outer level and TO is not supported.
87:
1.33 anton 88: require search.fs
1.14 anton 89: require float.fs
1.1 anton 90:
1.14 anton 91: : compile-@local ( n -- ) \ gforth compile-fetch-local
1.3 anton 92: case
1.7 pazsan 93: 0 of postpone @local0 endof
94: 1 cells of postpone @local1 endof
95: 2 cells of postpone @local2 endof
96: 3 cells of postpone @local3 endof
1.3 anton 97: ( otherwise ) dup postpone @local# ,
98: endcase ;
99:
1.14 anton 100: : compile-f@local ( n -- ) \ gforth compile-f-fetch-local
1.3 anton 101: case
1.7 pazsan 102: 0 of postpone f@local0 endof
103: 1 floats of postpone f@local1 endof
1.3 anton 104: ( otherwise ) dup postpone f@local# ,
105: endcase ;
106:
1.27 pazsan 107: \ locals stuff needed for control structures
108:
109: : compile-lp+! ( n -- ) \ gforth compile-l-p-plus-store
110: dup negate locals-size +!
111: 0 over = if
112: else -1 cells over = if postpone lp-
113: else 1 floats over = if postpone lp+
114: else 2 floats over = if postpone lp+2
115: else postpone lp+!# dup ,
116: then then then then drop ;
117:
118: : adjust-locals-size ( n -- ) \ gforth
119: \ sets locals-size to n and generates an appropriate lp+!
120: locals-size @ swap - compile-lp+! ;
121:
1.1 anton 122: \ the locals stack grows downwards (see primitives)
123: \ of the local variables of a group (in braces) the leftmost is on top,
124: \ i.e. by going onto the locals stack the order is reversed.
125: \ there are alignment gaps if necessary.
126: \ lp must have the strictest alignment (usually float) across calls;
127: \ for simplicity we align it strictly for every group.
128:
1.5 anton 129: slowvoc @
130: slowvoc on \ we want a linked list for the vocabulary locals
1.1 anton 131: vocabulary locals \ this contains the local variables
1.3 anton 132: ' locals >body ' locals-list >body !
1.5 anton 133: slowvoc !
1.1 anton 134:
135: create locals-buffer 1000 allot \ !! limited and unsafe
136: \ here the names of the local variables are stored
137: \ we would have problems storing them at the normal dp
138:
139: variable locals-dp \ so here's the special dp for locals.
140:
141: : alignlp-w ( n1 -- n2 )
142: \ cell-align size and generate the corresponding code for aligning lp
1.3 anton 143: aligned dup adjust-locals-size ;
1.1 anton 144:
145: : alignlp-f ( n1 -- n2 )
1.3 anton 146: faligned dup adjust-locals-size ;
1.1 anton 147:
148: \ a local declaration group (the braces stuff) is compiled by calling
149: \ the appropriate compile-pushlocal for the locals, starting with the
150: \ righmost local; the names are already created earlier, the
151: \ compile-pushlocal just inserts the offsets from the frame base.
152:
153: : compile-pushlocal-w ( a-addr -- ) ( run-time: w -- )
154: \ compiles a push of a local variable, and adjusts locals-size
155: \ stores the offset of the local variable to a-addr
156: locals-size @ alignlp-w cell+ dup locals-size !
157: swap !
158: postpone >l ;
159:
1.27 pazsan 160: \ locals list operations
161:
162: : common-list ( list1 list2 -- list3 ) \ gforth-internal
163: \ list1 and list2 are lists, where the heads are at higher addresses than
164: \ the tail. list3 is the largest sublist of both lists.
165: begin
166: 2dup u<>
167: while
168: 2dup u>
169: if
170: swap
171: then
172: @
173: repeat
174: drop ;
175:
176: : sub-list? ( list1 list2 -- f ) \ gforth-internal
177: \ true iff list1 is a sublist of list2
178: begin
179: 2dup u<
180: while
181: @
182: repeat
183: = ;
184:
185: : list-size ( list -- u ) \ gforth-internal
186: \ size of the locals frame represented by list
187: 0 ( list n )
188: begin
189: over 0<>
190: while
191: over
192: ((name>)) >body @ max
193: swap @ swap ( get next )
194: repeat
195: faligned nip ;
196:
197: : set-locals-size-list ( list -- )
198: dup locals-list !
199: list-size locals-size ! ;
200:
201: : check-begin ( list -- )
202: \ warn if list is not a sublist of locals-list
203: locals-list @ sub-list? 0= if
204: \ !! print current position
205: ." compiler was overly optimistic about locals at a BEGIN" cr
206: \ !! print assumption and reality
207: then ;
208:
1.1 anton 209: : compile-pushlocal-f ( a-addr -- ) ( run-time: f -- )
210: locals-size @ alignlp-f float+ dup locals-size !
211: swap !
212: postpone f>l ;
213:
214: : compile-pushlocal-d ( a-addr -- ) ( run-time: w1 w2 -- )
215: locals-size @ alignlp-w cell+ cell+ dup locals-size !
216: swap !
217: postpone swap postpone >l postpone >l ;
218:
219: : compile-pushlocal-c ( a-addr -- ) ( run-time: w -- )
1.3 anton 220: -1 chars compile-lp+!
1.1 anton 221: locals-size @ swap !
222: postpone lp@ postpone c! ;
223:
224: : create-local ( " name" -- a-addr )
1.9 anton 225: \ defines the local "name"; the offset of the local shall be
226: \ stored in a-addr
1.1 anton 227: create
1.12 anton 228: immediate restrict
1.1 anton 229: here 0 , ( place for the offset ) ;
230:
1.3 anton 231: : lp-offset ( n1 -- n2 )
232: \ converts the offset from the frame start to an offset from lp and
233: \ i.e., the address of the local is lp+locals_size-offset
234: locals-size @ swap - ;
235:
1.1 anton 236: : lp-offset, ( n -- )
237: \ converts the offset from the frame start to an offset from lp and
238: \ adds it as inline argument to a preceding locals primitive
1.3 anton 239: lp-offset , ;
1.1 anton 240:
241: vocabulary locals-types \ this contains all the type specifyers, -- and }
242: locals-types definitions
243:
1.14 anton 244: : W: ( "name" -- a-addr xt ) \ gforth w-colon
245: create-local
1.1 anton 246: \ xt produces the appropriate locals pushing code when executed
247: ['] compile-pushlocal-w
248: does> ( Compilation: -- ) ( Run-time: -- w )
249: \ compiles a local variable access
1.3 anton 250: @ lp-offset compile-@local ;
1.1 anton 251:
1.14 anton 252: : W^ ( "name" -- a-addr xt ) \ gforth w-caret
253: create-local
1.1 anton 254: ['] compile-pushlocal-w
255: does> ( Compilation: -- ) ( Run-time: -- w )
256: postpone laddr# @ lp-offset, ;
257:
1.14 anton 258: : F: ( "name" -- a-addr xt ) \ gforth f-colon
259: create-local
1.1 anton 260: ['] compile-pushlocal-f
261: does> ( Compilation: -- ) ( Run-time: -- w )
1.3 anton 262: @ lp-offset compile-f@local ;
1.1 anton 263:
1.14 anton 264: : F^ ( "name" -- a-addr xt ) \ gforth f-caret
265: create-local
1.1 anton 266: ['] compile-pushlocal-f
267: does> ( Compilation: -- ) ( Run-time: -- w )
268: postpone laddr# @ lp-offset, ;
269:
1.14 anton 270: : D: ( "name" -- a-addr xt ) \ gforth d-colon
271: create-local
1.1 anton 272: ['] compile-pushlocal-d
273: does> ( Compilation: -- ) ( Run-time: -- w )
274: postpone laddr# @ lp-offset, postpone 2@ ;
275:
1.14 anton 276: : D^ ( "name" -- a-addr xt ) \ gforth d-caret
277: create-local
1.1 anton 278: ['] compile-pushlocal-d
279: does> ( Compilation: -- ) ( Run-time: -- w )
280: postpone laddr# @ lp-offset, ;
281:
1.14 anton 282: : C: ( "name" -- a-addr xt ) \ gforth c-colon
283: create-local
1.1 anton 284: ['] compile-pushlocal-c
285: does> ( Compilation: -- ) ( Run-time: -- w )
286: postpone laddr# @ lp-offset, postpone c@ ;
287:
1.14 anton 288: : C^ ( "name" -- a-addr xt ) \ gforth c-caret
289: create-local
1.1 anton 290: ['] compile-pushlocal-c
291: does> ( Compilation: -- ) ( Run-time: -- w )
292: postpone laddr# @ lp-offset, ;
293:
294: \ you may want to make comments in a locals definitions group:
295: ' \ alias \ immediate
296: ' ( alias ( immediate
297:
298: forth definitions
299:
300: \ the following gymnastics are for declaring locals without type specifier.
301: \ we exploit a feature of our dictionary: every wordlist
302: \ has it's own methods for finding words etc.
303: \ So we create a vocabulary new-locals, that creates a 'w:' local named x
304: \ when it is asked if it contains x.
305:
306: also locals-types
307:
308: : new-locals-find ( caddr u w -- nfa )
309: \ this is the find method of the new-locals vocabulary
310: \ make a new local with name caddr u; w is ignored
311: \ the returned nfa denotes a word that produces what W: produces
312: \ !! do the whole thing without nextname
1.3 anton 313: drop nextname
314: ['] W: >name ;
1.1 anton 315:
316: previous
317:
318: : new-locals-reveal ( -- )
319: true abort" this should not happen: new-locals-reveal" ;
320:
1.22 anton 321: create new-locals-map ( -- wordlist-map )
1.29 anton 322: ' new-locals-find A,
323: ' new-locals-reveal A,
324: ' drop A, \ rehash method
1.34 jwilke 325: ' drop A,
1.1 anton 326:
1.27 pazsan 327: slowvoc @
328: slowvoc on
1.1 anton 329: vocabulary new-locals
1.27 pazsan 330: slowvoc !
1.1 anton 331: new-locals-map ' new-locals >body cell+ A! \ !! use special access words
332:
333: variable old-dpp
334:
335: \ and now, finally, the user interface words
1.32 anton 336: : { ( -- lastxt wid 0 ) \ gforth open-brace
1.1 anton 337: dp old-dpp !
338: locals-dp dpp !
1.32 anton 339: lastxt get-current
1.1 anton 340: also new-locals
1.32 anton 341: also locals definitions locals-types
1.1 anton 342: 0 TO locals-wordlist
343: 0 postpone [ ; immediate
344:
345: locals-types definitions
346:
1.32 anton 347: : } ( lastxt wid 0 a-addr1 xt1 ... -- ) \ gforth close-brace
1.1 anton 348: \ ends locals definitions
349: ] old-dpp @ dpp !
350: begin
351: dup
352: while
353: execute
354: repeat
355: drop
356: locals-size @ alignlp-f locals-size ! \ the strictest alignment
357: previous previous
1.32 anton 358: set-current lastcfa !
1.1 anton 359: locals-list TO locals-wordlist ;
360:
1.14 anton 361: : -- ( addr wid 0 ... -- ) \ gforth dash-dash
1.1 anton 362: }
1.9 anton 363: [char] } parse 2drop ;
1.1 anton 364:
365: forth definitions
366:
367: \ A few thoughts on automatic scopes for locals and how they can be
368: \ implemented:
369:
370: \ We have to combine locals with the control structures. My basic idea
371: \ was to start the life of a local at the declaration point. The life
372: \ would end at any control flow join (THEN, BEGIN etc.) where the local
373: \ is lot live on both input flows (note that the local can still live in
374: \ other, later parts of the control flow). This would make a local live
375: \ as long as you expected and sometimes longer (e.g. a local declared in
376: \ a BEGIN..UNTIL loop would still live after the UNTIL).
377:
378: \ The following example illustrates the problems of this approach:
379:
380: \ { z }
381: \ if
382: \ { x }
383: \ begin
384: \ { y }
385: \ [ 1 cs-roll ] then
386: \ ...
387: \ until
388:
389: \ x lives only until the BEGIN, but the compiler does not know this
390: \ until it compiles the UNTIL (it can deduce it at the THEN, because at
391: \ that point x lives in no thread, but that does not help much). This is
392: \ solved by optimistically assuming at the BEGIN that x lives, but
393: \ warning at the UNTIL that it does not. The user is then responsible
394: \ for checking that x is only used where it lives.
395:
396: \ The produced code might look like this (leaving out alignment code):
397:
398: \ >l ( z )
399: \ ?branch <then>
400: \ >l ( x )
401: \ <begin>:
402: \ >l ( y )
403: \ lp+!# 8 ( RIP: x,y )
404: \ <then>:
405: \ ...
406: \ lp+!# -4 ( adjust lp to <begin> state )
407: \ ?branch <begin>
408: \ lp+!# 4 ( undo adjust )
409:
410: \ The BEGIN problem also has another incarnation:
411:
412: \ AHEAD
413: \ BEGIN
414: \ x
415: \ [ 1 CS-ROLL ] THEN
416: \ { x }
417: \ ...
418: \ UNTIL
419:
420: \ should be legal: The BEGIN is not a control flow join in this case,
421: \ since it cannot be entered from the top; therefore the definition of x
422: \ dominates the use. But the compiler processes the use first, and since
423: \ it does not look ahead to notice the definition, it will complain
424: \ about it. Here's another variation of this problem:
425:
426: \ IF
427: \ { x }
428: \ ELSE
429: \ ...
430: \ AHEAD
431: \ BEGIN
432: \ x
433: \ [ 2 CS-ROLL ] THEN
434: \ ...
435: \ UNTIL
436:
437: \ In this case x is defined before the use, and the definition dominates
438: \ the use, but the compiler does not know this until it processes the
439: \ UNTIL. So what should the compiler assume does live at the BEGIN, if
440: \ the BEGIN is not a control flow join? The safest assumption would be
441: \ the intersection of all locals lists on the control flow
442: \ stack. However, our compiler assumes that the same variables are live
443: \ as on the top of the control flow stack. This covers the following case:
444:
445: \ { x }
446: \ AHEAD
447: \ BEGIN
448: \ x
449: \ [ 1 CS-ROLL ] THEN
450: \ ...
451: \ UNTIL
452:
453: \ If this assumption is too optimistic, the compiler will warn the user.
454:
1.28 anton 455: \ Implementation:
1.1 anton 456:
1.3 anton 457: \ explicit scoping
1.1 anton 458:
1.14 anton 459: : scope ( compilation -- scope ; run-time -- ) \ gforth
1.3 anton 460: cs-push-part scopestart ; immediate
461:
1.14 anton 462: : endscope ( compilation scope -- ; run-time -- ) \ gforth
1.3 anton 463: scope?
1.1 anton 464: drop
1.3 anton 465: locals-list @ common-list
466: dup list-size adjust-locals-size
467: locals-list ! ; immediate
1.1 anton 468:
1.3 anton 469: \ adapt the hooks
1.1 anton 470:
1.3 anton 471: : locals-:-hook ( sys -- sys addr xt n )
472: \ addr is the nfa of the defined word, xt its xt
1.1 anton 473: DEFERS :-hook
474: last @ lastcfa @
475: clear-leave-stack
476: 0 locals-size !
477: locals-buffer locals-dp !
1.3 anton 478: 0 locals-list !
479: dead-code off
480: defstart ;
1.1 anton 481:
1.3 anton 482: : locals-;-hook ( sys addr xt sys -- sys )
483: def?
1.1 anton 484: 0 TO locals-wordlist
1.3 anton 485: 0 adjust-locals-size ( not every def ends with an exit )
1.1 anton 486: lastcfa ! last !
487: DEFERS ;-hook ;
488:
1.28 anton 489: \ THEN (another control flow from before joins the current one):
490: \ The new locals-list is the intersection of the current locals-list and
491: \ the orig-local-list. The new locals-size is the (alignment-adjusted)
492: \ size of the new locals-list. The following code is generated:
493: \ lp+!# (current-locals-size - orig-locals-size)
494: \ <then>:
495: \ lp+!# (orig-locals-size - new-locals-size)
496:
497: \ Of course "lp+!# 0" is not generated. Still this is admittedly a bit
498: \ inefficient, e.g. if there is a locals declaration between IF and
499: \ ELSE. However, if ELSE generates an appropriate "lp+!#" before the
500: \ branch, there will be none after the target <then>.
501:
1.30 anton 502: : (then-like) ( orig -- )
503: dead-orig =
1.27 pazsan 504: if
1.30 anton 505: >resolve drop
1.27 pazsan 506: else
507: dead-code @
508: if
1.30 anton 509: >resolve set-locals-size-list dead-code off
1.27 pazsan 510: else \ both live
1.30 anton 511: over list-size adjust-locals-size
512: >resolve
1.27 pazsan 513: locals-list @ common-list dup list-size adjust-locals-size
514: locals-list !
515: then
516: then ;
517:
518: : (begin-like) ( -- )
519: dead-code @ if
520: \ set up an assumption of the locals visible here. if the
521: \ users want something to be visible, they have to declare
522: \ that using ASSUME-LIVE
523: backedge-locals @ set-locals-size-list
524: then
525: dead-code off ;
526:
527: \ AGAIN (the current control flow joins another, earlier one):
528: \ If the dest-locals-list is not a subset of the current locals-list,
529: \ issue a warning (see below). The following code is generated:
530: \ lp+!# (current-local-size - dest-locals-size)
531: \ branch <begin>
532:
533: : (again-like) ( dest -- addr )
534: over list-size adjust-locals-size
535: swap check-begin POSTPONE unreachable ;
536:
537: \ UNTIL (the current control flow may join an earlier one or continue):
538: \ Similar to AGAIN. The new locals-list and locals-size are the current
539: \ ones. The following code is generated:
540: \ ?branch-lp+!# <begin> (current-local-size - dest-locals-size)
541:
542: : (until-like) ( list addr xt1 xt2 -- )
543: \ list and addr are a fragment of a cs-item
544: \ xt1 is the conditional branch without lp adjustment, xt2 is with
545: >r >r
546: locals-size @ 2 pick list-size - dup if ( list dest-addr adjustment )
547: r> drop r> compile,
548: swap <resolve ( list adjustment ) ,
549: else ( list dest-addr adjustment )
550: drop
551: r> compile, <resolve
552: r> drop
553: then ( list )
554: check-begin ;
555:
556: : (exit-like) ( -- )
557: 0 adjust-locals-size ;
558:
1.1 anton 559: ' locals-:-hook IS :-hook
560: ' locals-;-hook IS ;-hook
1.27 pazsan 561:
562: ' (then-like) IS then-like
563: ' (begin-like) IS begin-like
564: ' (again-like) IS again-like
565: ' (until-like) IS until-like
566: ' (exit-like) IS exit-like
1.1 anton 567:
568: \ The words in the locals dictionary space are not deleted until the end
569: \ of the current word. This is a bit too conservative, but very simple.
570:
571: \ There are a few cases to consider: (see above)
572:
573: \ after AGAIN, AHEAD, EXIT (the current control flow is dead):
574: \ We have to special-case the above cases against that. In this case the
575: \ things above are not control flow joins. Everything should be taken
576: \ over from the live flow. No lp+!# is generated.
577:
578: \ About warning against uses of dead locals. There are several options:
579:
580: \ 1) Do not complain (After all, this is Forth;-)
581:
582: \ 2) Additional restrictions can be imposed so that the situation cannot
583: \ arise; the programmer would have to introduce explicit scoping
584: \ declarations in cases like the above one. I.e., complain if there are
585: \ locals that are live before the BEGIN but not before the corresponding
586: \ AGAIN (replace DO etc. for BEGIN and UNTIL etc. for AGAIN).
587:
588: \ 3) The real thing: i.e. complain, iff a local lives at a BEGIN, is
589: \ used on a path starting at the BEGIN, and does not live at the
590: \ corresponding AGAIN. This is somewhat hard to implement. a) How does
591: \ the compiler know when it is working on a path starting at a BEGIN
592: \ (consider "{ x } if begin [ 1 cs-roll ] else x endif again")? b) How
593: \ is the usage info stored?
594:
595: \ For now I'll resort to alternative 2. When it produces warnings they
596: \ will often be spurious, but warnings should be rare. And better
597: \ spurious warnings now and then than days of bug-searching.
598:
599: \ Explicit scoping of locals is implemented by cs-pushing the current
600: \ locals-list and -size (and an unused cell, to make the size equal to
601: \ the other entries) at the start of the scope, and restoring them at
602: \ the end of the scope to the intersection, like THEN does.
603:
604:
605: \ And here's finally the ANS standard stuff
606:
1.14 anton 607: : (local) ( addr u -- ) \ local paren-local-paren
1.3 anton 608: \ a little space-inefficient, but well deserved ;-)
609: \ In exchange, there are no restrictions whatsoever on using (local)
1.4 anton 610: \ as long as you use it in a definition
1.3 anton 611: dup
612: if
613: nextname POSTPONE { [ also locals-types ] W: } [ previous ]
614: else
615: 2drop
616: endif ;
1.1 anton 617:
1.4 anton 618: : >definer ( xt -- definer )
619: \ this gives a unique identifier for the way the xt was defined
620: \ words defined with different does>-codes have different definers
621: \ the definer can be used for comparison and in definer!
1.30 anton 622: dup >does-code
623: ?dup-if
624: nip 1 or
1.4 anton 625: else
626: >code-address
627: then ;
628:
629: : definer! ( definer xt -- )
630: \ gives the word represented by xt the behaviour associated with definer
631: over 1 and if
1.13 anton 632: swap [ 1 invert ] literal and does-code!
1.4 anton 633: else
634: code-address!
635: then ;
636:
1.23 pazsan 637: :noname
1.31 anton 638: ' dup >definer [ ' locals-wordlist ] literal >definer =
1.23 pazsan 639: if
640: >body !
641: else
642: -&32 throw
643: endif ;
644: :noname
1.21 anton 645: 0 0 0. 0.0e0 { c: clocal w: wlocal d: dlocal f: flocal }
1.28 anton 646: comp' drop dup >definer
1.21 anton 647: case
1.30 anton 648: [ ' locals-wordlist ] literal >definer \ value
1.21 anton 649: OF >body POSTPONE Aliteral POSTPONE ! ENDOF
1.35 ! anton 650: \ !! dependent on c: etc. being does>-defining words
! 651: \ this works, because >definer uses >does-code in this case,
! 652: \ which produces a relocatable address
! 653: [ comp' clocal drop >definer ] literal
1.21 anton 654: OF POSTPONE laddr# >body @ lp-offset, POSTPONE c! ENDOF
1.35 ! anton 655: [ comp' wlocal drop >definer ] literal
1.21 anton 656: OF POSTPONE laddr# >body @ lp-offset, POSTPONE ! ENDOF
1.35 ! anton 657: [ comp' dlocal drop >definer ] literal
1.21 anton 658: OF POSTPONE laddr# >body @ lp-offset, POSTPONE 2! ENDOF
1.35 ! anton 659: [ comp' flocal drop >definer ] literal
1.21 anton 660: OF POSTPONE laddr# >body @ lp-offset, POSTPONE f! ENDOF
661: -&32 throw
1.23 pazsan 662: endcase ;
1.24 anton 663: interpret/compile: TO ( c|w|d|r "name" -- ) \ core-ext,local
1.1 anton 664:
1.6 pazsan 665: : locals|
1.14 anton 666: \ don't use 'locals|'! use '{'! A portable and free '{'
1.21 anton 667: \ implementation is compat/anslocals.fs
1.8 anton 668: BEGIN
669: name 2dup s" |" compare 0<>
670: WHILE
671: (local)
672: REPEAT
1.14 anton 673: drop 0 (local) ; immediate restrict
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