Replace.cpp

   1 /* Cycript - Optimizing JavaScript Compiler/Runtime
   2  * Copyright (C) 2009-2013  Jay Freeman (saurik)
   3 */
   4
   5 /* GNU General Public License, Version 3 {{{ */
   6 /*
   7  * Cycript is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published
   9  * by the Free Software Foundation, either version 3 of the License,
  10  * or (at your option) any later version.
  11  *
  12  * Cycript is distributed in the hope that it will be useful, but
  13  * 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 Cycript.  If not, see <http://www.gnu.org/licenses/>.
  19 **/
  20 /* }}} */
  21
  22 #include "Parser.hpp"
  23 #include "Replace.hpp"
  24
  25 #include <iomanip>
  26
  27 CYFunctionExpression *CYNonLocalize(CYContext &context, CYFunctionExpression *function) {
  28     function->nonlocal_ = context.nextlocal_;
  29     return function;
  30 }
  31
  32 CYExpression *CYAdd::Replace(CYContext &context) {
  33     CYInfix::Replace(context);
  34
  35     CYString *lhs(dynamic_cast<CYString *>(lhs_));
  36     CYString *rhs(dynamic_cast<CYString *>(rhs_));
  37
  38     if (lhs != NULL || rhs != NULL) {
  39         if (lhs == NULL) {
  40             lhs = lhs_->String(context);
  41             if (lhs == NULL)
  42                 return this;
  43         } else if (rhs == NULL) {
  44             rhs = rhs_->String(context);
  45             if (rhs == NULL)
  46                 return this;
  47         }
  48
  49         return lhs->Concat(context, rhs);
  50     }
  51
  52     if (CYNumber *lhn = lhs_->Number(context))
  53         if (CYNumber *rhn = rhs_->Number(context))
  54             return $D(lhn->Value() + rhn->Value());
  55
  56     return this;
  57 }
  58
  59 CYExpression *CYAddressOf::Replace(CYContext &context) {
  60     return $C0($M(rhs_, $S("$cya")));
  61 }
  62
  63 CYArgument *CYArgument::Replace(CYContext &context) { $T(NULL)
  64     context.Replace(value_);
  65     next_ = next_->Replace(context);
  66
  67     if (value_ == NULL) {
  68         if (next_ == NULL)
  69             return NULL;
  70         else
  71             value_ = $U;
  72     }
  73
  74     return this;
  75 }
  76
  77 CYExpression *CYArray::Replace(CYContext &context) {
  78     elements_->Replace(context);
  79     return this;
  80 }
  81
  82 CYExpression *CYArrayComprehension::Replace(CYContext &context) {
  83     CYVariable *cyv($V("$cyv"));
  84
  85     return $C0($F(NULL, $P1($L("$cyv"), comprehensions_->Parameters(context)), $$->*
  86         $E($ CYAssign(cyv, $ CYArray()))->*
  87         comprehensions_->Replace(context, $E($C1($M(cyv, $S("push")), expression_)))->*
  88         $ CYReturn(cyv)
  89     ));
  90 }
  91
  92 CYExpression *CYAssignment::Replace(CYContext &context) {
  93     context.Replace(lhs_);
  94     context.Replace(rhs_);
  95     return this;
  96 }
  97
  98 CYStatement *CYBlock::Replace(CYContext &context) {
  99     context.ReplaceAll(statements_);
 100     if (statements_ == NULL)
 101         return $ CYEmpty();
 102     return this;
 103 }
 104
 105 CYStatement *CYBreak::Replace(CYContext &context) {
 106     return this;
 107 }
 108
 109 CYExpression *CYCall::AddArgument(CYContext &context, CYExpression *value) {
 110     CYArgument **argument(&arguments_);
 111     while (*argument != NULL)
 112         argument = &(*argument)->next_;
 113     *argument = $ CYArgument(value);
 114     return this;
 115 }
 116
 117 CYExpression *CYCall::Replace(CYContext &context) {
 118     context.Replace(function_);
 119     arguments_->Replace(context);
 120     return this;
 121 }
 122
 123 namespace cy {
 124 namespace Syntax {
 125
 126 void Catch::Replace(CYContext &context) { $T()
 127     CYScope scope(true, context, code_.statements_);
 128
 129     context.Replace(name_);
 130     context.scope_->Declare(context, name_, CYIdentifierCatch);
 131
 132     code_.Replace(context);
 133     scope.Close();
 134 }
 135
 136 } }
 137
 138 void CYClause::Replace(CYContext &context) { $T()
 139     context.Replace(case_);
 140     context.ReplaceAll(statements_);
 141     next_->Replace(context);
 142 }
 143
 144 CYStatement *CYComment::Replace(CYContext &context) {
 145     return this;
 146 }
 147
 148 CYExpression *CYCompound::Replace(CYContext &context) {
 149     if (next_ == NULL)
 150         return expression_;
 151
 152     context.Replace(expression_);
 153     context.Replace(next_);
 154
 155     if (CYCompound *compound = dynamic_cast<CYCompound *>(expression_)) {
 156         expression_ = compound->expression_;
 157         compound->expression_ = compound->next_;
 158         compound->next_ = next_;
 159         next_ = compound;
 160     }
 161
 162     return this;
 163 }
 164
 165 CYExpression *CYCompound::Primitive(CYContext &context) {
 166     CYExpression *expression(expression_);
 167     if (expression == NULL || next_ != NULL)
 168         return NULL;
 169     return expression->Primitive(context);
 170 }
 171
 172 CYFunctionParameter *CYComprehension::Parameters(CYContext &context) const { $T(NULL)
 173     CYFunctionParameter *next(next_->Parameters(context));
 174     if (CYFunctionParameter *parameter = Parameter(context)) {
 175         parameter->SetNext(next);
 176         return parameter;
 177     } else
 178         return next;
 179 }
 180
 181 CYStatement *CYComprehension::Replace(CYContext &context, CYStatement *statement) const {
 182     return next_ == NULL ? statement : next_->Replace(context, statement);
 183 }
 184
 185 CYExpression *CYCondition::Replace(CYContext &context) {
 186     context.Replace(test_);
 187     context.Replace(true_);
 188     context.Replace(false_);
 189     return this;
 190 }
 191
 192 void CYContext::NonLocal(CYStatement *&statements) {
 193     CYContext &context(*this);
 194
 195     if (nextlocal_ != NULL && nextlocal_->identifier_ != NULL) {
 196         CYIdentifier *cye($I("$cye")->Replace(context));
 197         CYIdentifier *unique(nextlocal_->identifier_->Replace(context));
 198
 199         CYStatement *declare(
 200             $ CYVar($L1($ CYDeclaration(unique, $ CYObject()))));
 201
 202         cy::Syntax::Catch *rescue(
 203             $ cy::Syntax::Catch(cye, $$->*
 204                 $ CYIf($ CYIdentical($M($V(cye), $S("$cyk")), $V(unique)), $$->*
 205                     $ CYReturn($M($V(cye), $S("$cyv"))))->*
 206                 $ cy::Syntax::Throw($V(cye))));
 207
 208         context.Replace(declare);
 209         rescue->Replace(context);
 210
 211         statements = $$->*
 212             declare->*
 213             $ cy::Syntax::Try(statements, rescue, NULL);
 214     }
 215 }
 216
 217 CYIdentifier *CYContext::Unique() {
 218     return $ CYIdentifier($pool.strcat("$cy", $pool.itoa(unique_++), NULL));
 219 }
 220
 221 CYStatement *CYContinue::Replace(CYContext &context) {
 222     return this;
 223 }
 224
 225 CYStatement *CYDebugger::Replace(CYContext &context) {
 226     return this;
 227 }
 228
 229 CYAssignment *CYDeclaration::Assignment(CYContext &context) {
 230     if (initialiser_ == NULL)
 231         return NULL;
 232
 233     CYAssignment *value($ CYAssign(Variable(context), initialiser_));
 234     initialiser_ = NULL;
 235     return value;
 236 }
 237
 238 CYVariable *CYDeclaration::Variable(CYContext &context) {
 239     return $V(identifier_);
 240 }
 241
 242 CYStatement *CYDeclaration::ForEachIn(CYContext &context, CYExpression *value) {
 243     return $ CYVar($L1($ CYDeclaration(identifier_, value)));
 244 }
 245
 246 CYExpression *CYDeclaration::Replace(CYContext &context) {
 247     context.Replace(identifier_);
 248     context.scope_->Declare(context, identifier_, CYIdentifierVariable);
 249     return Variable(context);
 250 }
 251
 252 void CYDeclarations::Replace(CYContext &context) { $T()
 253     declaration_->Replace(context);
 254     next_->Replace(context);
 255 }
 256
 257 CYProperty *CYDeclarations::Property(CYContext &context) { $T(NULL)
 258     return $ CYProperty(declaration_->identifier_, declaration_->initialiser_, next_->Property(context));
 259 }
 260
 261 CYFunctionParameter *CYDeclarations::Parameter(CYContext &context) { $T(NULL)
 262     return $ CYFunctionParameter($ CYDeclaration(declaration_->identifier_), next_->Parameter(context));
 263 }
 264
 265 CYArgument *CYDeclarations::Argument(CYContext &context) { $T(NULL)
 266     return $ CYArgument(declaration_->initialiser_, next_->Argument(context));
 267 }
 268
 269 CYCompound *CYDeclarations::Compound(CYContext &context) { $T(NULL)
 270     CYCompound *compound(next_->Compound(context));
 271     if (CYAssignment *assignment = declaration_->Assignment(context))
 272         compound = $ CYCompound(assignment, compound);
 273     return compound;
 274 }
 275
 276 CYExpression *CYDirectMember::Replace(CYContext &context) {
 277     context.Replace(object_);
 278     context.Replace(property_);
 279     return this;
 280 }
 281
 282 CYStatement *CYDoWhile::Replace(CYContext &context) {
 283     context.Replace(test_);
 284     context.Replace(code_);
 285     return this;
 286 }
 287
 288 void CYElement::Replace(CYContext &context) { $T()
 289     context.Replace(value_);
 290     next_->Replace(context);
 291 }
 292
 293 CYStatement *CYEmpty::Replace(CYContext &context) {
 294     return NULL;
 295 }
 296
 297 CYExpression *CYEncodedType::Replace(CYContext &context) {
 298     return typed_->Replace(context);
 299 }
 300
 301 CYStatement *CYExpress::Replace(CYContext &context) {
 302     while (CYExpress *express = dynamic_cast<CYExpress *>(next_)) {
 303         expression_ = $ CYCompound(expression_, express->expression_);
 304         SetNext(express->next_);
 305     }
 306
 307     context.Replace(expression_);
 308     if (expression_ == NULL)
 309         return $ CYEmpty();
 310
 311     return this;
 312 }
 313
 314 CYExpression *CYExpression::AddArgument(CYContext &context, CYExpression *value) {
 315     return $C1(this, value);
 316 }
 317
 318 CYExpression *CYExpression::ClassName(CYContext &context, bool object) {
 319     return this;
 320 }
 321
 322 CYStatement *CYExpression::ForEachIn(CYContext &context, CYExpression *value) {
 323     return $E($ CYAssign(this, value));
 324 }
 325
 326 CYAssignment *CYExpression::Assignment(CYContext &context) {
 327     return NULL;
 328 }
 329
 330 CYNumber *CYFalse::Number(CYContext &context) {
 331     return $D(0);
 332 }
 333
 334 CYString *CYFalse::String(CYContext &context) {
 335     return $S("false");
 336 }
 337
 338 CYExpression *CYFatArrow::Replace(CYContext &context) {
 339     CYFunctionExpression *function($ CYFunctionExpression(NULL, parameters_, code_));
 340     function->this_.SetNext(context.this_);
 341     return function;
 342 }
 343
 344 void CYFinally::Replace(CYContext &context) { $T()
 345     code_.Replace(context);
 346 }
 347
 348 CYStatement *CYFor::Replace(CYContext &context) {
 349     context.Replace(initialiser_);
 350     context.Replace(test_);
 351     context.Replace(increment_);
 352     context.Replace(code_);
 353     return this;
 354 }
 355
 356 CYCompound *CYForDeclarations::Replace(CYContext &context) {
 357     declarations_->Replace(context);
 358     return declarations_->Compound(context);
 359 }
 360
 361 // XXX: this still feels highly suboptimal
 362 CYStatement *CYForIn::Replace(CYContext &context) {
 363     if (CYAssignment *assignment = initialiser_->Assignment(context))
 364         return $ CYBlock($$->*
 365             $E(assignment)->*
 366             this
 367         );
 368
 369     context.Replace(initialiser_);
 370     context.Replace(set_);
 371     context.Replace(code_);
 372     return this;
 373 }
 374
 375 CYFunctionParameter *CYForInComprehension::Parameter(CYContext &context) const {
 376     return $ CYFunctionParameter($ CYDeclaration(name_));
 377 }
 378
 379 CYStatement *CYForInComprehension::Replace(CYContext &context, CYStatement *statement) const {
 380     return $ CYForIn($V(name_), set_, CYComprehension::Replace(context, statement));
 381 }
 382
 383 CYStatement *CYForOf::Replace(CYContext &context) {
 384     if (CYAssignment *assignment = initialiser_->Assignment(context))
 385         return $ CYBlock($$->*
 386             $E(assignment)->*
 387             this
 388         );
 389
 390     CYIdentifier *cys($I("$cys")), *cyt($I("$cyt"));
 391
 392     return $ CYLetStatement($L2($ CYDeclaration(cys, set_), $ CYDeclaration(cyt)), $$->*
 393         $ CYForIn($V(cyt), $V(cys), $ CYBlock($$->*
 394             initialiser_->ForEachIn(context, $M($V(cys), $V(cyt)))->*
 395             code_
 396         ))
 397     );
 398 }
 399
 400 CYFunctionParameter *CYForOfComprehension::Parameter(CYContext &context) const {
 401     return $ CYFunctionParameter($ CYDeclaration(name_));
 402 }
 403
 404 CYStatement *CYForOfComprehension::Replace(CYContext &context, CYStatement *statement) const {
 405     CYIdentifier *cys($I("cys"));
 406
 407     return $E($C0($F(NULL, $P1($L("$cys")), $$->*
 408         $E($ CYAssign($V(cys), set_))->*
 409         $ CYForIn($V(name_), $V(cys), $ CYBlock($$->*
 410             $E($ CYAssign($V(name_), $M($V(cys), $V(name_))))->*
 411             CYComprehension::Replace(context, statement)
 412         ))
 413     )));
 414 }
 415
 416 void CYFunction::Inject(CYContext &context) {
 417     context.Replace(name_);
 418     context.scope_->Declare(context, name_, CYIdentifierOther);
 419 }
 420
 421 void CYFunction::Replace_(CYContext &context, bool outer) {
 422     if (outer)
 423         Inject(context);
 424
 425     CYThisScope *_this(context.this_);
 426     context.this_ = CYGetLast(&this_);
 427
 428     CYNonLocal *nonlocal(context.nonlocal_);
 429     CYNonLocal *nextlocal(context.nextlocal_);
 430
 431     bool localize;
 432     if (nonlocal_ != NULL) {
 433         localize = false;
 434         context.nonlocal_ = nonlocal_;
 435     } else {
 436         localize = true;
 437         nonlocal_ = $ CYNonLocal();
 438         context.nextlocal_ = nonlocal_;
 439     }
 440
 441     CYScope scope(!localize, context, code_.statements_);
 442
 443     if (!outer && name_ != NULL)
 444         Inject(context);
 445
 446     parameters_->Replace(context, code_);
 447     code_.Replace(context);
 448
 449     if (CYIdentifier *identifier = this_.identifier_)
 450         code_.statements_ = $$->*
 451             $ CYVar($L1($ CYDeclaration(identifier, $ CYThis())))->*
 452             code_.statements_;
 453
 454     if (localize)
 455         context.NonLocal(code_.statements_);
 456
 457     context.nextlocal_ = nextlocal;
 458     context.nonlocal_ = nonlocal;
 459
 460     context.this_ = _this;
 461
 462     scope.Close();
 463 }
 464
 465 CYExpression *CYFunctionExpression::Replace(CYContext &context) {
 466     Replace_(context, false);
 467     return this;
 468 }
 469
 470 void CYFunctionParameter::Replace(CYContext &context, CYBlock &code) { $T()
 471     CYAssignment *assignment(initialiser_->Assignment(context));
 472     context.Replace(initialiser_);
 473
 474     next_->Replace(context, code);
 475
 476     if (assignment != NULL)
 477         // XXX: this cast is quite incorrect
 478         code.AddPrev($ CYIf($ CYIdentical($ CYTypeOf(dynamic_cast<CYExpression *>(initialiser_)), $S("undefined")), $$->*
 479             $E(assignment)
 480         ));
 481 }
 482
 483 CYStatement *CYFunctionStatement::Replace(CYContext &context) {
 484     Replace_(context, true);
 485     return this;
 486 }
 487
 488 CYIdentifier *CYIdentifier::Replace(CYContext &context) {
 489     if (replace_ != NULL && replace_ != this)
 490         return replace_->Replace(context);
 491     replace_ = context.scope_->Lookup(context, this);
 492     return replace_;
 493 }
 494
 495 CYStatement *CYIf::Replace(CYContext &context) {
 496     context.Replace(test_);
 497     context.Replace(true_);
 498     context.Replace(false_);
 499     return this;
 500 }
 501
 502 CYFunctionParameter *CYIfComprehension::Parameter(CYContext &context) const {
 503     return NULL;
 504 }
 505
 506 CYStatement *CYIfComprehension::Replace(CYContext &context, CYStatement *statement) const {
 507     return $ CYIf(test_, CYComprehension::Replace(context, statement));
 508 }
 509
 510 CYStatement *CYImport::Replace(CYContext &context) {
 511     return $ CYVar($L1($L(module_->part_->Word(), $C1($V("require"), module_->Replace(context, "/")))));
 512 }
 513
 514 CYExpression *CYIndirect::Replace(CYContext &context) {
 515     return $M(rhs_, $S("$cyi"));
 516 }
 517
 518 CYExpression *CYIndirectMember::Replace(CYContext &context) {
 519     return $M($ CYIndirect(object_), property_);
 520 }
 521
 522 CYExpression *CYInfix::Replace(CYContext &context) {
 523     context.Replace(lhs_);
 524     context.Replace(rhs_);
 525     return this;
 526 }
 527
 528 CYStatement *CYLabel::Replace(CYContext &context) {
 529     context.Replace(statement_);
 530     return this;
 531 }
 532
 533 CYExpression *CYLambda::Replace(CYContext &context) {
 534     return $N2($V("Functor"), $ CYFunctionExpression(NULL, parameters_->Parameters(context), statements_), parameters_->TypeSignature(context, typed_->Replace(context)));
 535 }
 536
 537 CYStatement *CYLetStatement::Replace(CYContext &context) {
 538     return $E($ CYCall(CYNonLocalize(context, $ CYFunctionExpression(NULL, declarations_->Parameter(context), code_)), declarations_->Argument(context)));
 539 }
 540
 541 CYString *CYModule::Replace(CYContext &context, const char *separator) const {
 542     if (next_ == NULL)
 543         return $ CYString(part_);
 544     return $ CYString($pool.strcat(next_->Replace(context, separator)->Value(), separator, part_->Word(), NULL));
 545 }
 546
 547 CYExpression *CYMultiply::Replace(CYContext &context) {
 548     CYInfix::Replace(context);
 549
 550     if (CYNumber *lhn = lhs_->Number(context))
 551         if (CYNumber *rhn = rhs_->Number(context))
 552             return $D(lhn->Value() * rhn->Value());
 553
 554     return this;
 555 }
 556
 557 namespace cy {
 558 namespace Syntax {
 559
 560 CYExpression *New::AddArgument(CYContext &context, CYExpression *value) {
 561     CYSetLast(arguments_) = $ CYArgument(value);
 562     return this;
 563 }
 564
 565 CYExpression *New::Replace(CYContext &context) {
 566     context.Replace(constructor_);
 567     arguments_->Replace(context);
 568     return this;
 569 }
 570
 571 } }
 572
 573 CYNumber *CYNull::Number(CYContext &context) {
 574     return $D(0);
 575 }
 576
 577 CYString *CYNull::String(CYContext &context) {
 578     return $S("null");
 579 }
 580
 581 CYNumber *CYNumber::Number(CYContext &context) {
 582     return this;
 583 }
 584
 585 CYString *CYNumber::String(CYContext &context) {
 586     // XXX: there is a precise algorithm for this
 587     return $S($pool.sprintf(24, "%.17g", Value()));
 588 }
 589
 590 CYExpression *CYObject::Replace(CYContext &context) {
 591     properties_->Replace(context);
 592     return this;
 593 }
 594
 595 CYExpression *CYPostfix::Replace(CYContext &context) {
 596     context.Replace(lhs_);
 597     return this;
 598 }
 599
 600 CYExpression *CYPrefix::Replace(CYContext &context) {
 601     context.Replace(rhs_);
 602     return this;
 603 }
 604
 605 // XXX: this is evil evil black magic. don't ask, don't tell... don't believe!
 606 #define MappingSet "0etnirsoalfucdphmgyvbxTwSNECAFjDLkMOIBPqzRH$_WXUVGYKQJZ"
 607 //#define MappingSet "0abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_"
 608
 609 namespace {
 610     struct IdentifierUsageLess :
 611         std::binary_function<CYIdentifier *, CYIdentifier *, bool>
 612     {
 613         _finline bool operator ()(CYIdentifier *lhs, CYIdentifier *rhs) const {
 614             if (lhs->usage_ != rhs->usage_)
 615                 return lhs->usage_ > rhs->usage_;
 616             return lhs < rhs;
 617         }
 618     };
 619
 620     typedef std::set<CYIdentifier *, IdentifierUsageLess> IdentifierUsages;
 621 }
 622
 623 void CYProgram::Replace(CYContext &context) {
 624     CYScope scope(true, context, statements_);
 625
 626     context.nextlocal_ = $ CYNonLocal();
 627     context.ReplaceAll(statements_);
 628     context.NonLocal(statements_);
 629
 630     scope.Close();
 631
 632     size_t offset(0);
 633
 634     CYCStringSet external;
 635     for (CYIdentifierValueSet::const_iterator i(scope.identifiers_.begin()); i != scope.identifiers_.end(); ++i)
 636         external.insert((*i)->Word());
 637
 638     IdentifierUsages usages;
 639
 640     if (offset < context.rename_.size())
 641         CYForEach (i, context.rename_[offset].identifier_)
 642             usages.insert(i);
 643
 644     // XXX: totalling the probable occurrences and sorting by them would improve the result
 645     for (CYIdentifierUsageVector::const_iterator i(context.rename_.begin()); i != context.rename_.end(); ++i, ++offset) {
 646         //std::cout << *i << ":" << (*i)->offset_ << std::endl;
 647
 648         const char *name;
 649
 650         if (context.options_.verbose_)
 651             name = $pool.strcat("$", $pool.itoa(offset), NULL);
 652         else {
 653             char id[8];
 654             id[7] = '\0';
 655
 656           id:
 657             unsigned position(7), local(offset + 1);
 658
 659             do {
 660                 unsigned index(local % (sizeof(MappingSet) - 1));
 661                 local /= sizeof(MappingSet) - 1;
 662                 id[--position] = MappingSet[index];
 663             } while (local != 0);
 664
 665             if (external.find(id + position) != external.end()) {
 666                 ++offset;
 667                 goto id;
 668             }
 669
 670             name = $pool.strmemdup(id + position, 7 - position);
 671             // XXX: at some point, this could become a keyword
 672         }
 673
 674         CYForEach (identifier, i->identifier_)
 675             identifier->Set(name);
 676     }
 677 }
 678
 679 void CYProperty::Replace(CYContext &context) { $T()
 680     context.Replace(value_);
 681     next_->Replace(context);
 682     if (value_ == NULL)
 683         value_ = $U;
 684 }
 685
 686 CYStatement *CYReturn::Replace(CYContext &context) {
 687     if (context.nonlocal_ != NULL) {
 688         CYProperty *value(value_ == NULL ? NULL : $ CYProperty($S("$cyv"), value_));
 689         return $ cy::Syntax::Throw($ CYObject(
 690             $ CYProperty($S("$cyk"), $V(context.nonlocal_->Target(context)), value)
 691         ));
 692     }
 693
 694     context.Replace(value_);
 695     return this;
 696 }
 697
 698 CYExpression *CYRubyBlock::Replace(CYContext &context) {
 699     // XXX: this needs to do something much more epic to handle return
 700     return call_->AddArgument(context, proc_->Replace(context));
 701 }
 702
 703 CYExpression *CYRubyProc::Replace(CYContext &context) {
 704     return CYNonLocalize(context, $ CYFunctionExpression(NULL, parameters_, code_));
 705 }
 706
 707 CYScope::CYScope(bool transparent, CYContext &context, CYStatement *&statements) :
 708     transparent_(transparent),
 709     context_(context),
 710     statements_(statements),
 711     parent_(context.scope_)
 712 {
 713     context_.scope_ = this;
 714 }
 715
 716 CYScope::~CYScope() {
 717 }
 718
 719 void CYScope::Close() {
 720     context_.scope_ = parent_;
 721     Scope(context_, statements_);
 722 }
 723
 724 void CYScope::Declare(CYContext &context, CYIdentifier *identifier, CYIdentifierFlags flags) {
 725     if (!transparent_ || flags == CYIdentifierArgument || flags == CYIdentifierCatch)
 726         internal_.insert(CYIdentifierAddressFlagsMap::value_type(identifier, flags));
 727     else if (parent_ != NULL)
 728         parent_->Declare(context, identifier, flags);
 729 }
 730
 731 CYIdentifier *CYScope::Lookup(CYContext &context, CYIdentifier *identifier) {
 732     std::pair<CYIdentifierValueSet::iterator, bool> insert(identifiers_.insert(identifier));
 733     return *insert.first;
 734 }
 735
 736 void CYScope::Merge(CYContext &context, CYIdentifier *identifier) {
 737     std::pair<CYIdentifierValueSet::iterator, bool> insert(identifiers_.insert(identifier));
 738     if (!insert.second) {
 739         if ((*insert.first)->offset_ < identifier->offset_)
 740             (*insert.first)->offset_ = identifier->offset_;
 741         identifier->replace_ = *insert.first;
 742         (*insert.first)->usage_ += identifier->usage_ + 1;
 743     }
 744 }
 745
 746 namespace {
 747     struct IdentifierOffset {
 748         size_t offset_;
 749         CYIdentifierFlags flags_;
 750         size_t usage_;
 751         CYIdentifier *identifier_;
 752
 753         IdentifierOffset(CYIdentifier *identifier, CYIdentifierFlags flags) :
 754             offset_(identifier->offset_),
 755             flags_(flags),
 756             usage_(identifier->usage_),
 757             identifier_(identifier)
 758         {
 759         }
 760     };
 761
 762     struct IdentifierOffsetLess :
 763         std::binary_function<const IdentifierOffset &, const IdentifierOffset &, bool>
 764     {
 765         _finline bool operator ()(const IdentifierOffset &lhs, const IdentifierOffset &rhs) const {
 766             if (lhs.offset_ != rhs.offset_)
 767                 return lhs.offset_ < rhs.offset_;
 768             if (lhs.flags_ != rhs.flags_)
 769                 return lhs.flags_ < rhs.flags_;
 770             /*if (lhs.usage_ != rhs.usage_)
 771                 return lhs.usage_ < rhs.usage_;*/
 772             return lhs.identifier_ < rhs.identifier_;
 773         }
 774     };
 775
 776     typedef std::set<IdentifierOffset, IdentifierOffsetLess> IdentifierOffsets;
 777 }
 778
 779 void CYScope::Scope(CYContext &context, CYStatement *&statements) {
 780     if (parent_ == NULL)
 781         return;
 782
 783     CYDeclarations *last(NULL), *curr(NULL);
 784
 785     IdentifierOffsets offsets;
 786
 787     for (CYIdentifierAddressFlagsMap::const_iterator i(internal_.begin()); i != internal_.end(); ++i)
 788         if (i->second != CYIdentifierMagic)
 789             offsets.insert(IdentifierOffset(i->first, i->second));
 790
 791     size_t offset(0);
 792
 793     for (IdentifierOffsets::const_iterator i(offsets.begin()); i != offsets.end(); ++i) {
 794         if (i->flags_ == CYIdentifierVariable) {
 795             CYDeclarations *next($ CYDeclarations($ CYDeclaration(i->identifier_)));
 796             if (last == NULL)
 797                 last = next;
 798             if (curr != NULL)
 799                 curr->SetNext(next);
 800             curr = next;
 801         }
 802
 803         if (offset < i->offset_)
 804             offset = i->offset_;
 805         if (context.rename_.size() <= offset)
 806             context.rename_.resize(offset + 1);
 807
 808         CYIdentifierUsage &rename(context.rename_[offset++]);
 809         i->identifier_->SetNext(rename.identifier_);
 810         rename.identifier_ = i->identifier_;
 811         rename.usage_ += i->identifier_->usage_ + 1;
 812     }
 813
 814     if (last != NULL) {
 815         CYVar *var($ CYVar(last));
 816         var->SetNext(statements);
 817         statements = var;
 818     }
 819
 820     for (CYIdentifierValueSet::const_iterator i(identifiers_.begin()); i != identifiers_.end(); ++i)
 821         if (internal_.find(*i) == internal_.end()) {
 822             //std::cout << *i << '=' << offset << std::endl;
 823             if ((*i)->offset_ < offset)
 824                 (*i)->offset_ = offset;
 825             parent_->Merge(context, *i);
 826         }
 827 }
 828
 829 CYString *CYString::Concat(CYContext &context, CYString *rhs) const {
 830     size_t size(size_ + rhs->size_);
 831     char *value($ char[size + 1]);
 832     memcpy(value, value_, size_);
 833     memcpy(value + size_, rhs->value_, rhs->size_);
 834     value[size] = '\0';
 835     return $S(value, size);
 836 }
 837
 838 CYNumber *CYString::Number(CYContext &context) {
 839     // XXX: there is a precise algorithm for this
 840     return NULL;
 841 }
 842
 843 CYString *CYString::String(CYContext &context) {
 844     return this;
 845 }
 846
 847 CYStatement *CYSwitch::Replace(CYContext &context) {
 848     context.Replace(value_);
 849     clauses_->Replace(context);
 850     return this;
 851 }
 852
 853 CYExpression *CYThis::Replace(CYContext &context) {
 854     if (context.this_ != NULL)
 855         return $V(context.this_->Identifier(context));
 856     return this;
 857 }
 858
 859 namespace cy {
 860 namespace Syntax {
 861
 862 CYStatement *Throw::Replace(CYContext &context) {
 863     context.Replace(value_);
 864     return this;
 865 }
 866
 867 } }
 868
 869 CYExpression *CYTrivial::Replace(CYContext &context) {
 870     return this;
 871 }
 872
 873 CYNumber *CYTrue::Number(CYContext &context) {
 874     return $D(1);
 875 }
 876
 877 CYString *CYTrue::String(CYContext &context) {
 878     return $S("true");
 879 }
 880
 881 namespace cy {
 882 namespace Syntax {
 883
 884 CYStatement *Try::Replace(CYContext &context) {
 885     code_.Replace(context);
 886     catch_->Replace(context);
 887     finally_->Replace(context);
 888     return this;
 889 }
 890
 891 } }
 892
 893 CYExpression *CYTypeArrayOf::Replace_(CYContext &context, CYExpression *type) {
 894     return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("arrayOf")), $ CYArgument(size_)));
 895 }
 896
 897 CYExpression *CYTypeBlockWith::Replace_(CYContext &context, CYExpression *type) {
 898     return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("blockWith")), parameters_->Argument(context)));
 899 }
 900
 901 CYExpression *CYTypeConstant::Replace_(CYContext &context, CYExpression *type) {
 902     return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("constant"))));
 903 }
 904
 905 CYStatement *CYTypeDefinition::Replace(CYContext &context) {
 906     return $E($ CYAssign($V(typed_->identifier_), typed_->Replace(context)));
 907 }
 908
 909 CYExpression *CYTypeError::Replace(CYContext &context) {
 910     _assert(false);
 911     return NULL;
 912 }
 913
 914 CYExpression *CYTypeModifier::Replace(CYContext &context, CYExpression *type) { $T(type)
 915     return Replace_(context, type);
 916 }
 917
 918 CYExpression *CYTypeFunctionWith::Replace_(CYContext &context, CYExpression *type) {
 919     return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("functionWith")), parameters_->Argument(context)));
 920 }
 921
 922 CYExpression *CYTypeLong::Replace(CYContext &context) {
 923     return $ CYCall($ CYDirectMember(specifier_->Replace(context), $ CYString("long")));
 924 }
 925
 926 CYExpression *CYTypePointerTo::Replace_(CYContext &context, CYExpression *type) {
 927     return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("pointerTo"))));
 928 }
 929
 930 CYExpression *CYTypeShort::Replace(CYContext &context) {
 931     return $ CYCall($ CYDirectMember(specifier_->Replace(context), $ CYString("short")));
 932 }
 933
 934 CYExpression *CYTypeSigned::Replace(CYContext &context) {
 935     return $ CYCall($ CYDirectMember(specifier_->Replace(context), $ CYString("signed")));
 936 }
 937
 938 CYExpression *CYTypeUnsigned::Replace(CYContext &context) {
 939     return $ CYCall($ CYDirectMember(specifier_->Replace(context), $ CYString("unsigned")));
 940 }
 941
 942 CYExpression *CYTypeVariable::Replace(CYContext &context) {
 943     return $V(name_);
 944 }
 945
 946 CYExpression *CYTypeVoid::Replace(CYContext &context) {
 947     return $N1($V("Type"), $ CYString("v"));
 948 }
 949
 950 CYExpression *CYTypeVolatile::Replace_(CYContext &context, CYExpression *type) {
 951     return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("volatile"))));
 952 }
 953
 954 CYExpression *CYTypedIdentifier::Replace(CYContext &context) {
 955     return modifier_->Replace(context, specifier_->Replace(context));
 956 }
 957
 958 CYArgument *CYTypedParameter::Argument(CYContext &context) { $T(NULL)
 959     return $ CYArgument(typed_->Replace(context), next_->Argument(context));
 960 }
 961
 962 CYFunctionParameter *CYTypedParameter::Parameters(CYContext &context) { $T(NULL)
 963     return $ CYFunctionParameter($ CYDeclaration(typed_->identifier_ ?: context.Unique()), next_->Parameters(context));
 964 }
 965
 966 CYExpression *CYTypedParameter::TypeSignature(CYContext &context, CYExpression *prefix) { $T(prefix)
 967     return next_->TypeSignature(context, $ CYAdd(prefix, typed_->Replace(context)));
 968 }
 969
 970 CYStatement *CYVar::Replace(CYContext &context) {
 971     declarations_->Replace(context);
 972     if (CYCompound *compound = declarations_->Compound(context))
 973         return $E(compound);
 974     return $ CYEmpty();
 975 }
 976
 977 CYExpression *CYVariable::Replace(CYContext &context) {
 978     context.Replace(name_);
 979     return this;
 980 }
 981
 982 CYStatement *CYWhile::Replace(CYContext &context) {
 983     context.Replace(test_);
 984     context.Replace(code_);
 985     return this;
 986 }
 987
 988 CYStatement *CYWith::Replace(CYContext &context) {
 989     context.Replace(scope_);
 990     context.Replace(code_);
 991     return this;
 992 }
 993
 994 CYExpression *CYWord::ClassName(CYContext &context, bool object) {
 995     CYString *name($S(this));
 996     if (object)
 997         return $C1($V("objc_getClass"), name);
 998     else
 999         return name;
1000 }