Replace.cpp

   1 /* Cycript - Optimizing JavaScript Compiler/Runtime
   2  * Copyright (C) 2009-2010  Jay Freeman (saurik)
   3 */
   4
   5 /* GNU Lesser General Public License, Version 3 {{{ */
   6 /*
   7  * Cycript is free software: you can redistribute it and/or modify it under
   8  * the terms of the GNU Lesser General Public License as published by the
   9  * Free Software Foundation, either version 3 of the License, or (at your
  10  * option) any later version.
  11  *
  12  * Cycript is distributed in the hope that it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  15  * License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser 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 CYExpression *CYAdd::Replace(CYContext &context) {
  28     CYInfix::Replace(context);
  29
  30     CYExpression *lhp(lhs_->Primitive(context));
  31     CYExpression *rhp(rhs_->Primitive(context));
  32
  33     CYString *lhs(dynamic_cast<CYString *>(lhp));
  34     CYString *rhs(dynamic_cast<CYString *>(rhp));
  35
  36     if (lhs != NULL || rhs != NULL) {
  37         if (lhs == NULL) {
  38             lhs = lhp->String(context);
  39             if (lhs == NULL)
  40                 return this;
  41         } else if (rhs == NULL) {
  42             rhs = rhp->String(context);
  43             if (rhs == NULL)
  44                 return this;
  45         }
  46
  47         return lhs->Concat(context, rhs);
  48     }
  49
  50     if (CYNumber *lhn = lhp->Number(context))
  51         if (CYNumber *rhn = rhp->Number(context))
  52             return $D(lhn->Value() + rhn->Value());
  53
  54     return this;
  55 }
  56
  57 CYExpression *CYAddressOf::Replace(CYContext &context) {
  58     CYPrefix::Replace(context);
  59     return $C0($M(rhs_, $S("$cya")));
  60 }
  61
  62 void CYArgument::Replace(CYContext &context) { $T()
  63     context.Replace(value_);
  64     next_->Replace(context);
  65 }
  66
  67 CYExpression *CYArray::Replace(CYContext &context) {
  68     elements_->Replace(context);
  69     return this;
  70 }
  71
  72 CYExpression *CYArrayComprehension::Replace(CYContext &context) {
  73     CYVariable *cyv($V("$cyv"));
  74
  75     return $C0($F(NULL, $P1("$cyv", comprehensions_->Parameters(context)), $$->*
  76         $E($ CYAssign(cyv, $ CYArray()))->*
  77         comprehensions_->Replace(context, $E($C1($M(cyv, $S("push")), expression_)))->*
  78         $ CYReturn(cyv)
  79     ));
  80 }
  81
  82 CYExpression *CYAssignment::Replace(CYContext &context) {
  83     context.Replace(lhs_);
  84     context.Replace(rhs_);
  85     return this;
  86 }
  87
  88 CYStatement *CYBlock::Replace(CYContext &context) {
  89     context.ReplaceAll(statements_);
  90     if (statements_ == NULL)
  91         return $ CYEmpty();
  92     return this;
  93 }
  94
  95 CYStatement *CYBreak::Replace(CYContext &context) {
  96     return this;
  97 }
  98
  99 CYExpression *CYCall::AddArgument(CYContext &context, CYExpression *value) {
 100     CYArgument **argument(&arguments_);
 101     while (*argument != NULL)
 102         argument = &(*argument)->next_;
 103     *argument = $ CYArgument(value);
 104     return this;
 105 }
 106
 107 CYExpression *CYCall::Replace(CYContext &context) {
 108     context.Replace(function_);
 109     arguments_->Replace(context);
 110     return this;
 111 }
 112
 113 namespace cy {
 114 namespace Syntax {
 115
 116 void Catch::Replace(CYContext &context) { $T()
 117     CYScope scope(CYScopeCatch, context, code_.statements_);
 118
 119     context.Replace(name_);
 120     context.scope_->Declare(context, name_, CYIdentifierCatch);
 121
 122     code_.Replace(context);
 123     scope.Close();
 124 }
 125
 126 } }
 127
 128 void CYClause::Replace(CYContext &context) { $T()
 129     context.Replace(case_);
 130     context.ReplaceAll(statements_);
 131     next_->Replace(context);
 132 }
 133
 134 CYStatement *CYComment::Replace(CYContext &context) {
 135     return this;
 136 }
 137
 138 CYExpression *CYCompound::Replace(CYContext &context) {
 139     context.ReplaceAll(expressions_);
 140     if (expressions_ == NULL)
 141         return NULL;
 142     return this;
 143 }
 144
 145 CYFunctionParameter *CYComprehension::Parameters(CYContext &context) const { $T(NULL)
 146     CYFunctionParameter *next(next_->Parameters(context));
 147     if (CYFunctionParameter *parameter = Parameter(context)) {
 148         parameter->SetNext(next);
 149         return parameter;
 150     } else
 151         return next;
 152 }
 153
 154 CYStatement *CYComprehension::Replace(CYContext &context, CYStatement *statement) const {
 155     return next_ == NULL ? statement : next_->Replace(context, statement);
 156 }
 157
 158 CYExpression *CYCondition::Replace(CYContext &context) {
 159     context.Replace(test_);
 160     context.Replace(true_);
 161     context.Replace(false_);
 162     return this;
 163 }
 164
 165 void CYContext::NonLocal(CYStatement *&statements) {
 166     CYContext &context(*this);
 167
 168     if (nextlocal_ != NULL && nextlocal_->identifier_ != NULL) {
 169         CYIdentifier *cye($I("$cye")->Replace(context));
 170         CYIdentifier *unique(nextlocal_->identifier_->Replace(context));
 171
 172         CYStatement *declare(
 173             $ CYVar($L1($L(unique, $ CYObject()))));
 174
 175         cy::Syntax::Catch *rescue(
 176             $ cy::Syntax::Catch(cye, $$->*
 177                 $ CYIf($ CYIdentical($M($V(cye), $S("$cyk")), $V(unique)), $$->*
 178                     $ CYReturn($M($V(cye), $S("$cyv"))))->*
 179                 $ cy::Syntax::Throw($V(cye))));
 180
 181         context.Replace(declare);
 182         rescue->Replace(context);
 183
 184         statements = $$->*
 185             declare->*
 186             $ cy::Syntax::Try(statements, rescue, NULL);
 187     }
 188 }
 189
 190 CYIdentifier *CYContext::Unique() {
 191     return $ CYIdentifier(apr_psprintf($pool, "$cy%u", unique_++));
 192 }
 193
 194 CYStatement *CYContinue::Replace(CYContext &context) {
 195     return this;
 196 }
 197
 198 CYAssignment *CYDeclaration::Assignment(CYContext &context) {
 199     CYExpression *variable(Replace(context));
 200     return initialiser_ == NULL ? NULL : $ CYAssign(variable, initialiser_);
 201 }
 202
 203 CYStatement *CYDeclaration::ForEachIn(CYContext &context, CYExpression *value) {
 204     return $ CYVar($L1($L(identifier_, value)));
 205 }
 206
 207 CYExpression *CYDeclaration::Replace(CYContext &context) {
 208     context.Replace(identifier_);
 209     context.scope_->Declare(context, identifier_, CYIdentifierVariable);
 210     return $V(identifier_);
 211 }
 212
 213 CYProperty *CYDeclarations::Property(CYContext &context) { $T(NULL)
 214     return $ CYProperty(declaration_->identifier_, declaration_->initialiser_ ?: $U, next_->Property(context));
 215 }
 216
 217 CYCompound *CYDeclarations::Replace(CYContext &context) {
 218     CYCompound *compound(next_ == NULL ? $ CYCompound() : next_->Replace(context));
 219     if (CYAssignment *assignment = declaration_->Assignment(context))
 220         compound->AddPrev(assignment);
 221     return compound;
 222 }
 223
 224 CYExpression *CYDirectMember::Replace(CYContext &context) {
 225     Replace_(context);
 226     return this;
 227 }
 228
 229 CYStatement *CYDoWhile::Replace(CYContext &context) {
 230     context.Replace(test_);
 231     context.Replace(code_);
 232     return this;
 233 }
 234
 235 void CYElement::Replace(CYContext &context) { $T()
 236     context.Replace(value_);
 237     next_->Replace(context);
 238 }
 239
 240 CYStatement *CYEmpty::Replace(CYContext &context) {
 241     return NULL;
 242 }
 243
 244 CYStatement *CYExpress::Replace(CYContext &context) {
 245     while (CYExpress *express = dynamic_cast<CYExpress *>(next_)) {
 246         CYCompound *compound(dynamic_cast<CYCompound *>(express->expression_));
 247         if (compound == NULL)
 248             compound = $ CYCompound(express->expression_);
 249         compound->AddPrev(expression_);
 250         expression_ = compound;
 251         SetNext(express->next_);
 252     }
 253
 254     context.Replace(expression_);
 255     if (expression_ == NULL)
 256         return $ CYEmpty();
 257
 258     return this;
 259 }
 260
 261 CYExpression *CYExpression::AddArgument(CYContext &context, CYExpression *value) {
 262     return $C1(this, value);
 263 }
 264
 265 CYExpression *CYExpression::ClassName(CYContext &context, bool object) {
 266     return this;
 267 }
 268
 269 CYStatement *CYExpression::ForEachIn(CYContext &context, CYExpression *value) {
 270     return $E($ CYAssign(this, value));
 271 }
 272
 273 CYNumber *CYFalse::Number(CYContext &context) {
 274     return $D(0);
 275 }
 276
 277 CYString *CYFalse::String(CYContext &context) {
 278     return $S("false");
 279 }
 280
 281 void CYFinally::Replace(CYContext &context) { $T()
 282     code_.Replace(context);
 283 }
 284
 285 CYStatement *CYFor::Replace(CYContext &context) {
 286     context.Replace(initialiser_);
 287     context.Replace(test_);
 288     context.Replace(increment_);
 289     context.Replace(code_);
 290     return this;
 291 }
 292
 293 CYStatement *CYForIn::Replace(CYContext &context) {
 294     // XXX: this actually might need a prefix statement
 295     context.Replace(initialiser_);
 296     context.Replace(set_);
 297     context.Replace(code_);
 298     return this;
 299 }
 300
 301 CYFunctionParameter *CYForInComprehension::Parameter(CYContext &context) const {
 302     return $ CYFunctionParameter(name_);
 303 }
 304
 305 CYStatement *CYForInComprehension::Replace(CYContext &context, CYStatement *statement) const {
 306     return $ CYForIn($V(name_), set_, CYComprehension::Replace(context, statement));
 307 }
 308
 309 CYStatement *CYForEachIn::Replace(CYContext &context) {
 310     CYIdentifier *cys($I("$cys")), *cyt($I("$cyt"));
 311
 312     return $ CYLet($L2($L(cys, set_), $L(cyt)), $$->*
 313         $ CYForIn($V(cyt), $V(cys), $ CYBlock($$->*
 314             initialiser_->ForEachIn(context, $M($V(cys), $V(cyt)))->*
 315             code_
 316         ))
 317     );
 318 }
 319
 320 CYFunctionParameter *CYForEachInComprehension::Parameter(CYContext &context) const {
 321     return $ CYFunctionParameter(name_);
 322 }
 323
 324 CYStatement *CYForEachInComprehension::Replace(CYContext &context, CYStatement *statement) const {
 325     CYIdentifier *cys($I("cys"));
 326
 327     return $E($C0($F(NULL, $P1("$cys"), $$->*
 328         $E($ CYAssign($V(cys), set_))->*
 329         $ CYForIn($V(name_), $V(cys), $ CYBlock($$->*
 330             $E($ CYAssign($V(name_), $M($V(cys), $V(name_))))->*
 331             CYComprehension::Replace(context, statement)
 332         ))
 333     )));
 334 }
 335
 336 void CYFunction::Inject(CYContext &context) {
 337     context.Replace(name_);
 338     context.scope_->Declare(context, name_, CYIdentifierOther);
 339 }
 340
 341 void CYFunction::Replace_(CYContext &context, bool outer) {
 342     if (outer)
 343         Inject(context);
 344
 345     CYScope scope(CYScopeFunction, context, code_.statements_);
 346
 347     CYNonLocal *nonlocal(context.nonlocal_);
 348     CYNonLocal *nextlocal(context.nextlocal_);
 349
 350     bool localize;
 351     if (nonlocal_ != NULL) {
 352         localize = false;
 353         context.nonlocal_ = nonlocal_;
 354     } else {
 355         localize = true;
 356         nonlocal_ = $ CYNonLocal();
 357         context.nextlocal_ = nonlocal_;
 358     }
 359
 360     if (!outer && name_ != NULL)
 361         Inject(context);
 362
 363     if (parameters_ != NULL)
 364         parameters_ = parameters_->Replace(context, code_);
 365
 366     code_.Replace(context);
 367
 368     if (localize)
 369         context.NonLocal(code_.statements_);
 370
 371     context.nextlocal_ = nextlocal;
 372     context.nonlocal_ = nonlocal;
 373
 374     scope.Close();
 375 }
 376
 377 CYExpression *CYFunctionExpression::Replace(CYContext &context) {
 378     Replace_(context, false);
 379     return this;
 380 }
 381
 382 CYFunctionParameter *CYFunctionParameter::Replace(CYContext &context, CYBlock &code) {
 383     context.Replace(name_);
 384     context.scope_->Declare(context, name_, CYIdentifierArgument);
 385     if (next_ != NULL)
 386         next_ = next_->Replace(context, code);
 387     return this;
 388 }
 389
 390 CYStatement *CYFunctionStatement::Replace(CYContext &context) {
 391     Replace_(context, true);
 392     return this;
 393 }
 394
 395 CYIdentifier *CYIdentifier::Replace(CYContext &context) {
 396     if (replace_ != NULL && replace_ != this)
 397         return replace_->Replace(context);
 398     replace_ = context.scope_->Lookup(context, this);
 399     return replace_;
 400 }
 401
 402 CYStatement *CYIf::Replace(CYContext &context) {
 403     context.Replace(test_);
 404     context.Replace(true_);
 405     context.Replace(false_);
 406     return this;
 407 }
 408
 409 CYFunctionParameter *CYIfComprehension::Parameter(CYContext &context) const {
 410     return NULL;
 411 }
 412
 413 CYStatement *CYIfComprehension::Replace(CYContext &context, CYStatement *statement) const {
 414     return $ CYIf(test_, CYComprehension::Replace(context, statement));
 415 }
 416
 417 CYExpression *CYIndirect::Replace(CYContext &context) {
 418     CYPrefix::Replace(context);
 419     return $M(rhs_, $S("$cyi"));
 420 }
 421
 422 CYExpression *CYIndirectMember::Replace(CYContext &context) {
 423     Replace_(context);
 424     return $M($ CYIndirect(object_), property_);
 425 }
 426
 427 CYExpression *CYInfix::Replace(CYContext &context) {
 428     context.Replace(lhs_);
 429     context.Replace(rhs_);
 430     return this;
 431 }
 432
 433 CYStatement *CYLabel::Replace(CYContext &context) {
 434     context.Replace(statement_);
 435     return this;
 436 }
 437
 438 CYStatement *CYLet::Replace(CYContext &context) {
 439     return $ CYWith($ CYObject(declarations_->Property(context)), &code_);
 440 }
 441
 442 void CYMember::Replace_(CYContext &context) {
 443     context.Replace(object_);
 444     context.Replace(property_);
 445 }
 446
 447 namespace cy {
 448 namespace Syntax {
 449
 450 CYExpression *New::AddArgument(CYContext &context, CYExpression *value) {
 451     CYSetLast(arguments_, $ CYArgument(value));
 452     return this;
 453 }
 454
 455 CYExpression *New::Replace(CYContext &context) {
 456     context.Replace(constructor_);
 457     arguments_->Replace(context);
 458     return this;
 459 }
 460
 461 } }
 462
 463 CYNumber *CYNull::Number(CYContext &context) {
 464     return $D(0);
 465 }
 466
 467 CYString *CYNull::String(CYContext &context) {
 468     return $S("null");
 469 }
 470
 471 CYNumber *CYNumber::Number(CYContext &context) {
 472     return this;
 473 }
 474
 475 CYString *CYNumber::String(CYContext &context) {
 476     // XXX: there is a precise algorithm for this
 477     return $S(apr_psprintf($pool, "%.17g", Value()));
 478 }
 479
 480 CYExpression *CYObject::Replace(CYContext &context) {
 481     properties_->Replace(context);
 482     return this;
 483 }
 484
 485 CYFunctionParameter *CYOptionalFunctionParameter::Replace(CYContext &context, CYBlock &code) {
 486     CYFunctionParameter *parameter($ CYFunctionParameter(name_, next_));
 487     parameter = parameter->Replace(context, code);
 488     context.Replace(initializer_);
 489
 490     CYVariable *name($V(name_));
 491     code.AddPrev($ CYIf($ CYIdentical($ CYTypeOf(name), $S("undefined")), $$->*
 492         $E($ CYAssign(name, initializer_))
 493     ));
 494
 495     return parameter;
 496 }
 497
 498 CYExpression *CYPostfix::Replace(CYContext &context) {
 499     context.Replace(lhs_);
 500     return this;
 501 }
 502
 503 CYExpression *CYPrefix::Replace(CYContext &context) {
 504     context.Replace(rhs_);
 505     return this;
 506 }
 507
 508 // XXX: this is evil evil black magic. don't ask, don't tell... don't believe!
 509 #define MappingSet "0etnirsoalfucdphmgyvbxTwSNECAFjDLkMOIBPqzRH$_WXUVGYKQJZ"
 510 //#define MappingSet "0abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_"
 511
 512 namespace {
 513     struct IdentifierUsageLess :
 514         std::binary_function<CYIdentifier *, CYIdentifier *, bool>
 515     {
 516         _finline bool operator ()(CYIdentifier *lhs, CYIdentifier *rhs) const {
 517             if (lhs->usage_ != rhs->usage_)
 518                 return lhs->usage_ > rhs->usage_;
 519             return lhs < rhs;
 520         }
 521     };
 522
 523     typedef std::set<CYIdentifier *, IdentifierUsageLess> IdentifierUsages;
 524 }
 525
 526 void CYProgram::Replace(CYContext &context) {
 527     CYScope scope(CYScopeProgram, context, statements_);
 528
 529     context.nextlocal_ = $ CYNonLocal();
 530     context.ReplaceAll(statements_);
 531     context.NonLocal(statements_);
 532
 533     scope.Close();
 534
 535     size_t offset(0);
 536
 537     CYCStringSet external;
 538     for (CYIdentifierValueSet::const_iterator i(scope.identifiers_.begin()); i != scope.identifiers_.end(); ++i)
 539         external.insert((*i)->Word());
 540
 541     IdentifierUsages usages;
 542
 543     if (offset < context.rename_.size())
 544         CYForEach (i, context.rename_[offset].identifier_)
 545             usages.insert(i);
 546
 547     // XXX: totalling the probable occurrences and sorting by them would improve the result
 548     for (CYIdentifierUsageVector::const_iterator i(context.rename_.begin()); i != context.rename_.end(); ++i, ++offset) {
 549         //std::cout << *i << ":" << (*i)->offset_ << std::endl;
 550
 551         const char *name;
 552
 553         if (context.options_.verbose_)
 554             name = apr_psprintf($pool, "$%"APR_SIZE_T_FMT"", offset);
 555         else {
 556             char id[8];
 557             id[7] = '\0';
 558
 559           id:
 560             unsigned position(7), local(offset + 1);
 561
 562             do {
 563                 unsigned index(local % (sizeof(MappingSet) - 1));
 564                 local /= sizeof(MappingSet) - 1;
 565                 id[--position] = MappingSet[index];
 566             } while (local != 0);
 567
 568             if (external.find(id + position) != external.end()) {
 569                 ++offset;
 570                 goto id;
 571             }
 572
 573             name = apr_pstrmemdup($pool, id + position, 7 - position);
 574             // XXX: at some point, this could become a keyword
 575         }
 576
 577         CYForEach (identifier, i->identifier_)
 578             identifier->Set(name);
 579     }
 580 }
 581
 582 void CYProperty::Replace(CYContext &context) { $T()
 583     context.Replace(value_);
 584     next_->Replace(context);
 585 }
 586
 587 CYStatement *CYReturn::Replace(CYContext &context) {
 588     if (context.nonlocal_ != NULL) {
 589         CYProperty *value(value_ == NULL ? NULL : $ CYProperty($S("$cyv"), value_));
 590         return $ cy::Syntax::Throw($ CYObject(
 591             $ CYProperty($S("$cyk"), $V(context.nonlocal_->Target(context)), value)
 592         ));
 593     }
 594
 595     context.Replace(value_);
 596     return this;
 597 }
 598
 599 CYExpression *CYRubyBlock::Replace(CYContext &context) {
 600     // XXX: this needs to do something much more epic to handle return
 601     return call_->AddArgument(context, proc_->Replace(context));
 602 }
 603
 604 CYExpression *CYRubyProc::Replace(CYContext &context) {
 605     CYFunctionExpression *function($ CYFunctionExpression(NULL, parameters_, code_));
 606     function->nonlocal_ = context.nextlocal_;
 607     return function;
 608 }
 609
 610 CYScope::CYScope(CYScopeType type, CYContext &context, CYStatement *&statements) :
 611     type_(type),
 612     context_(context),
 613     statements_(statements),
 614     parent_(context.scope_)
 615 {
 616     context_.scope_ = this;
 617 }
 618
 619 CYScope::~CYScope() {
 620 }
 621
 622 void CYScope::Close() {
 623     context_.scope_ = parent_;
 624     Scope(context_, statements_);
 625 }
 626
 627 void CYScope::Declare(CYContext &context, CYIdentifier *identifier, CYIdentifierFlags flags) {
 628     if (type_ == CYScopeCatch && flags != CYIdentifierCatch)
 629         parent_->Declare(context, identifier, flags);
 630     else
 631         internal_.insert(CYIdentifierAddressFlagsMap::value_type(identifier, flags));
 632 }
 633
 634 CYIdentifier *CYScope::Lookup(CYContext &context, CYIdentifier *identifier) {
 635     std::pair<CYIdentifierValueSet::iterator, bool> insert(identifiers_.insert(identifier));
 636     return *insert.first;
 637 }
 638
 639 void CYScope::Merge(CYContext &context, CYIdentifier *identifier) {
 640     std::pair<CYIdentifierValueSet::iterator, bool> insert(identifiers_.insert(identifier));
 641     if (!insert.second) {
 642         if ((*insert.first)->offset_ < identifier->offset_)
 643             (*insert.first)->offset_ = identifier->offset_;
 644         identifier->replace_ = *insert.first;
 645         (*insert.first)->usage_ += identifier->usage_ + 1;
 646     }
 647 }
 648
 649 namespace {
 650     struct IdentifierOffset {
 651         size_t offset_;
 652         CYIdentifierFlags flags_;
 653         size_t usage_;
 654         CYIdentifier *identifier_;
 655
 656         IdentifierOffset(CYIdentifier *identifier, CYIdentifierFlags flags) :
 657             offset_(identifier->offset_),
 658             flags_(flags),
 659             usage_(identifier->usage_),
 660             identifier_(identifier)
 661         {
 662         }
 663     };
 664
 665     struct IdentifierOffsetLess :
 666         std::binary_function<const IdentifierOffset &, const IdentifierOffset &, bool>
 667     {
 668         _finline bool operator ()(const IdentifierOffset &lhs, const IdentifierOffset &rhs) const {
 669             if (lhs.offset_ != rhs.offset_)
 670                 return lhs.offset_ < rhs.offset_;
 671             if (lhs.flags_ != rhs.flags_)
 672                 return lhs.flags_ < rhs.flags_;
 673             /*if (lhs.usage_ != rhs.usage_)
 674                 return lhs.usage_ < rhs.usage_;*/
 675             return lhs.identifier_ < rhs.identifier_;
 676         }
 677     };
 678
 679     typedef std::set<IdentifierOffset, IdentifierOffsetLess> IdentifierOffsets;
 680 }
 681
 682 void CYScope::Scope(CYContext &context, CYStatement *&statements) {
 683     if (parent_ == NULL)
 684         return;
 685
 686     CYDeclarations *last(NULL), *curr(NULL);
 687
 688     IdentifierOffsets offsets;
 689
 690     for (CYIdentifierAddressFlagsMap::const_iterator i(internal_.begin()); i != internal_.end(); ++i)
 691         if (i->second != CYIdentifierMagic)
 692             offsets.insert(IdentifierOffset(i->first, i->second));
 693
 694     size_t offset(0);
 695
 696     for (IdentifierOffsets::const_iterator i(offsets.begin()); i != offsets.end(); ++i) {
 697         if (i->flags_ == CYIdentifierVariable) {
 698             CYDeclarations *next($ CYDeclarations($ CYDeclaration(i->identifier_)));
 699             if (last == NULL)
 700                 last = next;
 701             if (curr != NULL)
 702                 curr->SetNext(next);
 703             curr = next;
 704         }
 705
 706         if (offset < i->offset_)
 707             offset = i->offset_;
 708         if (context.rename_.size() <= offset)
 709             context.rename_.resize(offset + 1);
 710
 711         CYIdentifierUsage &rename(context.rename_[offset++]);
 712         i->identifier_->SetNext(rename.identifier_);
 713         rename.identifier_ = i->identifier_;
 714         rename.usage_ += i->identifier_->usage_ + 1;
 715     }
 716
 717     if (last != NULL) {
 718         CYVar *var($ CYVar(last));
 719         var->SetNext(statements);
 720         statements = var;
 721     }
 722
 723     for (CYIdentifierValueSet::const_iterator i(identifiers_.begin()); i != identifiers_.end(); ++i)
 724         if (internal_.find(*i) == internal_.end()) {
 725             //std::cout << *i << '=' << offset << std::endl;
 726             if ((*i)->offset_ < offset)
 727                 (*i)->offset_ = offset;
 728             parent_->Merge(context, *i);
 729         }
 730 }
 731
 732 CYString *CYString::Concat(CYContext &context, CYString *rhs) const {
 733     size_t size(size_ + rhs->size_);
 734     char *value($ char[size + 1]);
 735     memcpy(value, value_, size_);
 736     memcpy(value + size_, rhs->value_, rhs->size_);
 737     value[size] = '\0';
 738     return $S(value, size);
 739 }
 740
 741 CYNumber *CYString::Number(CYContext &context) {
 742     // XXX: there is a precise algorithm for this
 743     return NULL;
 744 }
 745
 746 CYString *CYString::String(CYContext &context) {
 747     return this;
 748 }
 749
 750 CYStatement *CYSwitch::Replace(CYContext &context) {
 751     context.Replace(value_);
 752     clauses_->Replace(context);
 753     return this;
 754 }
 755
 756 CYExpression *CYThis::Replace(CYContext &context) {
 757     return this;
 758 }
 759
 760 namespace cy {
 761 namespace Syntax {
 762
 763 CYStatement *Throw::Replace(CYContext &context) {
 764     context.Replace(value_);
 765     return this;
 766 }
 767
 768 } }
 769
 770 CYExpression *CYTrivial::Replace(CYContext &context) {
 771     return this;
 772 }
 773
 774 CYNumber *CYTrue::Number(CYContext &context) {
 775     return $D(1);
 776 }
 777
 778 CYString *CYTrue::String(CYContext &context) {
 779     return $S("true");
 780 }
 781
 782 namespace cy {
 783 namespace Syntax {
 784
 785 CYStatement *Try::Replace(CYContext &context) {
 786     code_.Replace(context);
 787     catch_->Replace(context);
 788     finally_->Replace(context);
 789     return this;
 790 }
 791
 792 } }
 793
 794 CYStatement *CYVar::Replace(CYContext &context) {
 795     return $E(declarations_->Replace(context));
 796 }
 797
 798 CYExpression *CYVariable::Replace(CYContext &context) {
 799     context.Replace(name_);
 800     return this;
 801 }
 802
 803 CYStatement *CYWhile::Replace(CYContext &context) {
 804     context.Replace(test_);
 805     context.Replace(code_);
 806     return this;
 807 }
 808
 809 CYStatement *CYWith::Replace(CYContext &context) {
 810     context.Replace(scope_);
 811     context.Replace(code_);
 812     return this;
 813 }
 814
 815 CYExpression *CYWord::ClassName(CYContext &context, bool object) {
 816     CYString *name($S(this));
 817     if (object)
 818         return $C1($V("objc_getClass"), name);
 819     else
 820         return name;
 821 }