aboutsummaryrefslogtreecommitdiff
path: root/src/interp/i-eval.boot
blob: 1432aa8e549c231d0737859102addda9aaf40eae (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
-- Copyright (c) 1991-2002, The Numerical ALgorithms Group Ltd.
-- All rights reserved.
-- Copyright (C) 2007-2012, Gabriel Dos Reis.
-- All rights reserved.
--
-- Redistribution and use in source and binary forms, with or without
-- modification, are permitted provided that the following conditions are
-- met:
--
--     - Redistributions of source code must retain the above copyright
--       notice, this list of conditions and the following disclaimer.
--
--     - Redistributions in binary form must reproduce the above copyright
--       notice, this list of conditions and the following disclaimer in
--       the documentation and/or other materials provided with the
--       distribution.
--
--     - Neither the name of The Numerical ALgorithms Group Ltd. nor the
--       names of its contributors may be used to endorse or promote products
--       derived from this software without specific prior written permission.
--
-- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
-- IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
-- TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
-- PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
-- OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
-- EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
-- PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
-- PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
-- LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
-- NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
-- SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


import i_-analy
namespace BOOT

--% Constructor Evaluation

$noEvalTypeMsg := nil

evalDomain form ==
  startTimingProcess 'instantiation
  newType? form => form
  form is ['%store,:.] => eval form
  result := eval mkEvalable form
  stopTimingProcess 'instantiation
  result

mkEvalable form ==
  form is [op,:argl] =>
    op is 'QUOTE => form
    op is ":" => [op,second form,mkEvalable third form]
    op is "WRAPPED" => mkEvalable devaluate argl
    op in '(Record Union Mapping) =>
      [op,:[mkEvalable arg for arg in argl]]
    op is 'Enumeration => form
    -- a niladic constructor instantiation goes by itself
    constructor? op and argl = nil => form
    loadIfNecessary op
    kind:= getConstructorKindFromDB op
    cosig := getDualSignature op =>
      [op,:[val for x in argl for typeFlag in cosig.source]] where val() ==
        typeFlag =>
          kind = "category" => MKQ x
          vector? x => MKQ x
          loadIfNecessary x
          mkEvalable x
        x is ['QUOTE,:.] => x
        x is ['_#,y] => ['SIZE,MKQ y]
        MKQ x
    [op,:[mkEvalable x for x in argl]]
  form=$EmptyMode => $Integer
  ident? form and constructor?(form) => [form]
  FBPIP form => BPINAME form
  form

evaluateType0 form ==
  -- Takes a parsed, unabbreviated type and evaluates it, replacing
  --  type valued variables with their values, and calling bottomUp
  --  on non-type valued arguemnts to the constructor
  --  and finally checking to see whether the type satisfies the
  --  conditions of its modemap
  -- However, the input might be an attribute, not a type
  -- $noEvalTypeMsg: local := true
  domain:= isDomainValuedVariable form => domain
  form = $EmptyMode => form
  form = "?"        => $EmptyMode
  string? form => form
  form = "$" => form
  $expandSegments : local := nil
  form is ['typeOf,.] =>
    form' := mkAtree form
    bottomUp form'
    objVal getValue(form')
  form is [op,:argl] =>
    op in '(Enumeration EnumerationCategory) => form
    op is 'CATEGORY =>
      argl is [x,:sigs] => [op,x,:[evaluateSignature(s) for s in sigs]]
      form
    op is ":" => [op,first argl,evaluateType second argl]
    builtinConstructor? op => [op,:[evaluateType arg for arg in argl]]
    constructor? op => evaluateType1 form
    nil
  ident? form and niladicConstructor? form => evaluateType [form]
  ident? form and (constructor? form or builtinConstructor? form) =>
    throwEvalTypeMsg("S2IE0003",[form,form])

++ Check for duplicate fields in a Union or Record domain form.
checkRecordOrUnionFields body ==
  for [[.,n,.],:fields] in tails body repeat
    for field in fields | field is [.,=n,.] repeat
      throwKeyedMsg("S2IL0030",[n])
  body

evaluateType form ==
  -- Takes a parsed, unabbreviated type and evaluates it, replacing
  --  type valued variables with their values, and calling bottomUp
  --  on non-type valued arguemnts to the constructor
  --  and finally checking to see whether the type satisfies the
  --  conditions of its modemap
  form is "$" => form
  form is "%" => "$"   --FIXME we should switch to "%" wholesale
  form = $EmptyMode => form
  form is "?"        => $EmptyMode
  string? form => form
  domain := isDomainValuedVariable form => domain
  $expandSegments : local := nil
  form is ['typeOf,.] =>
    objVal getValue elaborateForm form
  form is [op,:argl] =>
    op='CATEGORY =>
      argl is [x,:sigs] => [op,x,:[evaluateSignature(s) for s in sigs]]
      form
    op in '(Join Mapping) =>
      [op,:[evaluateType arg for arg in argl]]
    op='Union  =>
      argl and first argl is [x,.,.] and member(x,'(_: Declare)) =>
        [op, : checkRecordOrUnionFields
           [[":",sel,evaluateType type] for ['_:,sel,type] in argl]]
      [op,:[evaluateType arg for arg in argl]]
    op='Record =>
      [op, : checkRecordOrUnionFields
         [['_:,sel,evaluateType type] for ['_:,sel,type] in argl]]
    op='Enumeration => 
      -- only symbols, and they must not be repeated.
      for arg in argl repeat
        ident? arg => nil
        throwKeyedMsg("S2IL0031",nil)
      for [arg,:args] in tails argl repeat
        symbolMember?(arg,args) => throwKeyedMsg("S2IL0032",[arg])
      form
    op is ":" and argl is [x,t] => [op,x,evaluateType t]
    evaluateFormAsType form
  ident? form and niladicConstructor? form => evaluateType [form]
  ident? form and (constructor? form or builtinConstructor? form) =>
    throwEvalTypeMsg("S2IE0003",[form,form])
  evaluateFormAsType form

++ `form' used in a context where a type (domain or category) is
++ expected.  Attempt to fully evaluate it.  Error if the resulting
++ value is not a type.  When successful, the result is the reified
++ canonical form of the type.
evaluateFormAsType form ==
  form is [op,:args] and constructor? op => evaluateType1 form
  form is [op,:args] and ident? op and builtinConstructor? op =>
    [op,:[evaluateFormAsType x for x in args]]
  t := mkAtree form
  -- ??? Maybe we should be more careful about generalized types.
  bottomUp t is [m] and (member(m,$LangSupportTypes) or isCategoryForm(m,$e)) =>
    objVal getValue t
  throwEvalTypeMsg("S2IE0004",[form])

++ evaluates the arguments passed to the constructor `op'.
++ Note: only constructor instantiations go here.
evaluateType1 (form is [op,:argl]) ==
  null (sig := getConstructorSignature op) =>
     throwEvalTypeMsg("S2IE0005",[form])
  [.,:ml] := sig
  ml := replaceSharps(ml,form)
  # argl ~= #ml => throwEvalTypeMsg("S2IE0003",[form,form])
  for x in argl for m in ml for argnum in 1.. repeat
    typeList := [v,:typeList] where v() ==
      categoryForm?(m) =>
	m := evaluateType substitute(x,'_$,m)
	evalCategory(x' := (evaluateType x), m) => x'
	throwEvalTypeMsg("S2IE0004",[form])
      m := evaluateType m
      getConstructorKindFromDB opOf m = "domain" and 
	  (tree := mkAtree x) and  putTarget(tree,m) and ((bottomUp tree) is [m1]) =>
	      [zt,:zv]:= z1:= getAndEvalConstructorArgument tree
	      (v' := coerceOrRetract(z1,m)) => objValUnwrap v'
	      throwKeyedMsgCannotCoerceWithValue(zv,zt,m)
      if x = $EmptyMode then x := $quadSymbol
      throwEvalTypeMsg("S2IE0006",[makeOrdinal argnum,m,form])
  [op,:reverse! typeList]

throwEvalTypeMsg(msg, args) ==
  $noEvalTypeMsg => spadThrow()
  throwKeyedMsg(msg, args)

makeOrdinal i ==
  ('(first second third fourth fifth sixth seventh eighth ninth tenth)).(i-1)

evaluateSignature sig ==
  -- calls evaluateType on a signature
  sig is ['SIGNATURE,fun,sigl,:q] =>
    ['SIGNATURE,fun,
      [(t = '_$ => t; evaluateType(t)) for t in sigl],:q]
  sig

--% Code Evaluation

-- This code generates, then evaluates code during the bottom up phase
-- of interpretation

splitIntoBlocksOf200 a ==
  null a => nil
  [[first (r:=x) for x in tails a for i in 1..200],
    :splitIntoBlocksOf200 rest r]

evalForm(op,opName,argl,mmS) ==
  -- applies the first applicable function
  for mm in mmS until form repeat
    [sig,fun,cond]:= mm
    (first sig) = 'interpOnly => form := first sig
    #argl ~= #CDDR sig => 'skip ---> RDJ 6/95
    form:=
      $genValue or null cond =>
        [getArgValue2(x,t,sideEffectedArg?(t,sig,opName),opName) or return nil
         for x in argl for t in CDDR sig]
      [getArgValueComp2(x,t,c,sideEffectedArg?(t,sig,opName),opName) or return nil
        for x in argl for t in CDDR sig for c in cond]
    form or null argl =>
      dc:= first sig
      form :=
        dc='local => --[fun,:form]
          fun isnt [.,:.] =>
            isLocallyBound fun => ['SPADCALL,:form,fun]
            [fun,:form,nil]
          ['SPADCALL,:form,fun]
        dc is ["__FreeFunction__",:freeFun] =>
          ['SPADCALL,:form,freeFun]
        fun is ['XLAM,xargs,:xbody] =>
          rec :=  first form
          ['%funcall,['%function, ['%lambda,xargs,:xbody]],:take(#xargs, form)]
        dcVector := evalDomain dc
        fun0 :=
          newType? CAAR mm =>
            mm' := first ncSigTransform mm
            ncGetFunction(opName, first mm', rest mm')
          compileEvalForm(opName,fun,dcVector)
        null fun0 => throwKeyedMsg("S2IE0008",[opName])
        [bpi,:domain] := fun0
        sameObject?(bpi,function Undef) =>
         sayKeyedMsg("S2IE0009",[opName,formatSignature rest sig,first sig])
         nil
        if $NRTmonitorIfTrue then
          sayBrightlyNT ['"Applying ",first fun0,'" to:"]
          pp [devaluateDeeply x for x in form]
        $: local := domain
        ['SPADCALL, :form, fun0]
  not form => nil
--  not form => throwKeyedMsg("S2IE0008",[opName])
  form='interpOnly => rewriteMap(op,opName,argl)
  targetType := second sig
  if CONTAINED('_#,targetType) then targetType := NRTtypeHack targetType
  evalFormMkValue(op,form,targetType)

sideEffectedArg?(t,sig,opName) ==
  opString := symbolName opName
  (opName ~= 'setelt) and (opString.(#opString-1) ~= char "!") => nil
  dc := first sig
  t = dc

getArgValue(a, t) ==
  a isnt [.,:.] and not vector? a =>
    t' := coerceOrRetract(getBasicObject a,t)
    t' and getValueNormalForm t'
  v := getArgValue1(a, t) => v
  alt := altTypeOf(objMode getValue a, a, nil) =>
    t' := coerceInt(getValue a, alt)
    t' := coerceOrRetract(t',t)
    t' and getValueNormalForm t'
  nil

getArgValue1(a,t) ==
  -- creates a value for a, coercing to t
  t' := getValue(a) =>
    (m := getMode a) and (m is ['Mapping,:ml]) and (m = t) and
      objValUnwrap(t') is ["%Map",:.] =>
        getMappingArgValue(a,t,m)
    t' := coerceOrRetract(t',t)
    t' and getValueNormalForm t'
  systemErrorHere '"getArgValue1"

getArgValue2(a,t,se?,opName) ==
  se? and (objMode(getValue a) ~= t) =>
    throwKeyedMsg("S2IE0013", [opName, objMode(getValue a), t])
  getArgValue(a,t)

getArgValueOrThrow(x, type) ==
  getArgValue(x,type) or throwKeyedMsg("S2IC0007",[type])

getMappingArgValue(a,t,m is ['Mapping,:ml]) ==
  isLocallyBound(una := getUnname a) =>
    $genValue =>
      name := get(una,'name,$env)
      a.0 := name
      mmS := selectLocalMms(a,name,rest ml, nil)
      or/[mm for mm in mmS |
        (mm is [[., :ml1],oldName,:.] and ml=ml1)] => MKQ [oldName]
      nil
    una
  mmS := selectLocalMms(a,una,rest ml, nil)
  or/[mm for mm in mmS |
    (mm is [[., :ml1],oldName,:.] and ml=ml1)] => MKQ [oldName]
  nil

getArgValueComp2(arg, type, cond, se?, opName) ==
  se? and (objMode(getValue arg) ~= type) =>
    throwKeyedMsg("S2IE0013", [opName, objMode(getValue arg), type])
  getArgValueComp(arg, type, cond)

getArgValueComp(arg,type,cond) ==
  -- getArgValue for compiled case.  if there is a condition then
  --  v must be data to verify that coerceInteractive succeeds.
  v:= getArgValue(arg,type)
  null v => nil
  null cond => v
  v is ['QUOTE,:.] or getBasicMode v => v
  n := getUnnameIfCan arg
  if num := isSharpVarWithNum n then
    not $compilingMap => n := 'unknownVar
    alias := get($mapName,'alias,$e)
    n := alias.(num - 1)
  keyedMsgCompFailure("S2IE0010",[n])

evalFormMkValue(op,form,tm) ==
  val := object(form,tm)
  if $NRTmonitorIfTrue then
    sayBrightlyNT ['"Value of ",op.0,'" ===> "]
    pp objValUnwrap val
  putValue(op,val)
  [tm]

failCheck x ==
  x is '"failed" =>
    stopTimingProcess peekTimedName()
    THROW('interpreter,objNewWrap('"failed",$String))
  x = $coerceFailure =>
    nil
  x

--% Some Antique Comments About the Interpreter

--EVAL BOOT contains the top level interface to the Scratchhpad-II
--interpreter.  The Entry point into the interpreter from the parser is
--processInteractive.
--The type analysis algorithm is contained in the file BOTMUP BOOT,
--and MODSEL boot,
--the map handling routines are in MAP BOOT and NEWMAP BOOT, and
--the interactive coerce routines are in COERCE BOOT and COERCEFN BOOT.
--
--Conventions:
--    All spad values in the interpreter are passed around in triples.
--    These are lists of three items: [value,mode,environment].  The value
--    may be wrapped (this is a pair whose CAR is the atom WRAPPED and
--    whose CDR is the value), which indicates that it is a real value,
--    or unwrapped in which case it needs to be EVALed to produce the
--    proper value.  The mode is the type of value, and should always be
--    completely specified (not contain $EmptyMode).  The environment
--    is always empty, and is included for historical reasons.
--
--Modemaps:
--    Modemaps are descriptions of compiled Spad function which the
--    interpreter uses to perform type analysis. They consist of patterns
--    of types for the arguments, and conditions the types must satisfy
--    for the function to apply.  For each function name there is a list
--    of modemaps in file MODEMAP DATABASE for each distinct function with
--    that name. The following is the list of the modemaps for "*"
--    (multiplication. The first modemap (the one with the labels) is for
--    module mltiplication which is multiplication of an element of a
--    module by a member of its scalar domain.
--
--   This is the signature pattern for the modemap, it is of the form:
--    (DomainOfComputation TargetType <ArgumentType ...>)
--          |
--          |                This is the predicate that needs to be
--          |                 satisfied for the modemap to apply
--          |                            |
--          V                            |
--     /-----------/                     |
-- ( ( (*1 *1 *2 *1)                     V
--       /-----------------------------------------------------------/
--     ( (AND (ofCategory *1 (Module *2)) (ofCategory *2 (SimpleRing))) )
--      . CATDEF) <-- This is the file where the function was defined
--   ( (*1 *1 *2 *1)
--     ( (AND (isDomain *2 (Integer)) (ofCategory *1 (AbelianGroup))) )
--      . CATDEF)
--   ( (*1 *1 *2 *1)
--     ( (AND
--         (isDomain *2 (NonNegativeInteger))
--         (ofCategory *1 (AbelianMonoid))) )
--      . CATDEF)
--   ((*1 *1 *1 *1) ((ofCategory *1 (SemiGroup)) ) . CATDEF)
--      )
--
--Environments:
--    Environments associate properties with atoms.
--    (see CUTIL BOOT for the exact structure of environments).
--    Some common properties are:
-- modeSet:
--    During interpretation we build a modeSet property for each node in
--    the expression.  This is (in theory) a list of all the types
--    possible for the node.  In the current implementation these
--    modeSets always contain a single type.
-- value:
--    Value properties are always triples.  This is where the values of
--    variables are stored.  We also build value properties for internal
--    nodes during the bottom up phase.
-- mode:
--    This is the declared type of an identifier.
--
--  There are several different environments used in the interpreter:
--    $InteractiveFrame : this is the environment where the user
--     values are stored.  Any side effects of evaluation of a top-level
--     expression are stored in this environment.  It is always used as
--     the starting environment for interpretation.
--    $e : This is the name used for $InteractiveFrame while interpreting.
--    $env : This is local environment used by the interpreter.
--     Only temporary information (such as types of local variables is
--     stored in $env.
--     It is thrown away after evaluation of each expression.
--
--Frequently used global variables:
--    $genValue : if true then evaluate generated code, otherwise leave
--      code unevaluated.  If $genValue is false then we are compiling.
--    $op: name of the top level operator (unused except in map printing)
--    $mapList:  list of maps being type analyzed, used in recursive
--               map type anlysis.
--    $compilingMap: true when compiling a map, used to detect where to
--                   THROW when interpret-only is invoked
--    $compilingLoop: true when compiling a loop body, used to control
--                    nesting level of interp-only loop CATCH points
--    $interpOnly: true when in interpret only mode, used to call
--                 alternate forms of COLLECT and REPEAT.
--    $inCOLLECT: true when compiling a COLLECT, used only for hacked
--                stream compiler.
--    $StreamFrame: used in printing streams, it is the environment
--                  where local stream variables are stored
--    $declaredMode: Weak type propagation for symbols, set in upCOERCE
--                   and up%LET.  This variable is used to determine
--                   the alternate polynomial types of Symbols.
--    $localVars: list of local variables in a map body
--    $MapArgumentTypeList: hack for stream compilation