X-Git-Url: https://git.saurik.com/cycript.git/blobdiff_plain/e06e5ee1f12b9b79b34570e65c1f5e9c12b9b8c3..f3e85e94d4edaeb0d219e41c227adf7a75d84e9f:/Replace.cpp

diff --git a/Replace.cpp b/Replace.cpp
index d40c8f3..46dd8bb 100644
--- a/Replace.cpp
+++ b/Replace.cpp
@@ -1,50 +1,65 @@
-/* Cycript - Optimizing JavaScript Compiler/Runtime
- * Copyright (C) 2009-2012  Jay Freeman (saurik)
+/* Cycript - The Truly Universal Scripting Language
+ * Copyright (C) 2009-2016  Jay Freeman (saurik)
 */
 
-/* GNU Lesser General Public License, Version 3 {{{ */
+/* GNU Affero General Public License, Version 3 {{{ */
 /*
- * Cycript is free software: you can redistribute it and/or modify it under
- * the terms of the GNU Lesser General Public License as published by the
- * Free Software Foundation, either version 3 of the License, or (at your
- * option) any later version.
- *
- * Cycript is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
- * License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public License
- * along with Cycript.  If not, see <http://www.gnu.org/licenses/>.
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 **/
 /* }}} */
 
-#include "Parser.hpp"
-#include "Replace.hpp"
-
 #include <iomanip>
+#include <map>
+
+#include "Replace.hpp"
+#include "Syntax.hpp"
 
 CYFunctionExpression *CYNonLocalize(CYContext &context, CYFunctionExpression *function) {
     function->nonlocal_ = context.nextlocal_;
     return function;
 }
 
+CYFunctionExpression *CYSuperize(CYContext &context, CYFunctionExpression *function) {
+    function->super_ = context.super_;
+    return function;
+}
+
+CYStatement *CYDefineProperty(CYExpression *object, CYExpression *name, bool configurable, bool enumerable, CYProperty *descriptor) {
+    return $E($C3($M($V("Object"), $S("defineProperty")), object, name, $ CYObject(CYList<CYProperty>()
+        ->* (configurable ? $ CYPropertyValue($S("configurable"), $ CYTrue()) : NULL)
+        ->* (enumerable ? $ CYPropertyValue($S("enumerable"), $ CYTrue()) : NULL)
+        ->* descriptor)));
+}
+
+static void CYImplicitReturn(CYStatement *&code) {
+    if (CYStatement *&last = CYGetLast(code))
+        last = last->Return();
+}
+
 CYExpression *CYAdd::Replace(CYContext &context) {
     CYInfix::Replace(context);
 
-    CYExpression *lhp(lhs_->Primitive(context));
-    CYExpression *rhp(rhs_->Primitive(context));
-
-    CYString *lhs(dynamic_cast<CYString *>(lhp));
-    CYString *rhs(dynamic_cast<CYString *>(rhp));
+    CYString *lhs(dynamic_cast<CYString *>(lhs_));
+    CYString *rhs(dynamic_cast<CYString *>(rhs_));
 
     if (lhs != NULL || rhs != NULL) {
         if (lhs == NULL) {
-            lhs = lhp->String(context);
+            lhs = lhs_->String(context);
             if (lhs == NULL)
                 return this;
         } else if (rhs == NULL) {
-            rhs = rhp->String(context);
+            rhs = rhs_->String(context);
             if (rhs == NULL)
                 return this;
         }
@@ -52,8 +67,8 @@ CYExpression *CYAdd::Replace(CYContext &context) {
         return lhs->Concat(context, rhs);
     }
 
-    if (CYNumber *lhn = lhp->Number(context))
-        if (CYNumber *rhn = rhp->Number(context))
+    if (CYNumber *lhn = lhs_->Number(context))
+        if (CYNumber *rhn = rhs_->Number(context))
             return $D(lhn->Value() + rhn->Value());
 
     return this;
@@ -63,6 +78,14 @@ CYExpression *CYAddressOf::Replace(CYContext &context) {
     return $C0($M(rhs_, $S("$cya")));
 }
 
+CYTarget *CYApply::AddArgument(CYContext &context, CYExpression *value) {
+    CYArgument **argument(&arguments_);
+    while (*argument != NULL)
+        argument = &(*argument)->next_;
+    *argument = $ CYArgument(value);
+    return this;
+}
+
 CYArgument *CYArgument::Replace(CYContext &context) { $T(NULL)
     context.Replace(value_);
     next_ = next_->Replace(context);
@@ -77,47 +100,51 @@ CYArgument *CYArgument::Replace(CYContext &context) { $T(NULL)
     return this;
 }
 
-CYExpression *CYArray::Replace(CYContext &context) {
-    elements_->Replace(context);
+CYTarget *CYArray::Replace(CYContext &context) {
+    CYForEach (element, elements_)
+        element->Replace(context);
     return this;
 }
 
-CYExpression *CYArrayComprehension::Replace(CYContext &context) {
-    CYVariable *cyv($V("$cyv"));
+CYTarget *CYArrayComprehension::Replace(CYContext &context) {
+    CYIdentifier *cyv(context.Unique());
 
-    return $C0($F(NULL, $P1($L("$cyv"), comprehensions_->Parameters(context)), $$->*
-        $E($ CYAssign(cyv, $ CYArray()))->*
-        comprehensions_->Replace(context, $E($C1($M(cyv, $S("push")), expression_)))->*
-        $ CYReturn(cyv)
+    return $C0($F(NULL, $P1($B(cyv), comprehensions_->Parameters(context)), $$
+        ->* $E($ CYAssign($V(cyv), $ CYArray()))
+        ->* comprehensions_->Replace(context, $E($C1($M($V(cyv), $S("push")), expression_)))
+        ->* $ CYReturn($V(cyv))
     ));
 }
 
 CYExpression *CYAssignment::Replace(CYContext &context) {
+    // XXX: this is a horrible hack but I'm a month over schedule :(
+    if (CYSubscriptMember *subscript = dynamic_cast<CYSubscriptMember *>(lhs_))
+        return $C2($M(subscript->object_, $S("$cys")), subscript->property_, rhs_);
     context.Replace(lhs_);
     context.Replace(rhs_);
     return this;
 }
 
-CYStatement *CYBlock::Replace(CYContext &context) {
-    context.ReplaceAll(statements_);
-    if (statements_ == NULL)
-        return $ CYEmpty();
+CYStatement *CYBlock::Return() {
+    CYImplicitReturn(code_);
     return this;
 }
 
-CYStatement *CYBreak::Replace(CYContext &context) {
+CYStatement *CYBlock::Replace(CYContext &context) {
+    CYScope scope(true, context);
+    context.ReplaceAll(code_);
+    scope.Close(context);
+
+    if (code_ == NULL)
+        return $ CYEmpty();
     return this;
 }
 
-CYExpression *CYCall::AddArgument(CYContext &context, CYExpression *value) {
-    CYArgument **argument(&arguments_);
-    while (*argument != NULL)
-        argument = &(*argument)->next_;
-    *argument = $ CYArgument(value);
+CYStatement *CYBreak::Replace(CYContext &context) {
     return this;
 }
 
-CYExpression *CYCall::Replace(CYContext &context) {
+CYTarget *CYCall::Replace(CYContext &context) {
     context.Replace(function_);
     arguments_->Replace(context);
     return this;
@@ -127,41 +154,87 @@ namespace cy {
 namespace Syntax {
 
 void Catch::Replace(CYContext &context) { $T()
-    CYScope scope(true, context, code_.statements_);
+    CYScope scope(true, context);
 
-    context.Replace(name_);
-    context.scope_->Declare(context, name_, CYIdentifierCatch);
+    name_ = name_->Replace(context, CYIdentifierCatch);
 
-    code_.Replace(context);
-    scope.Close();
+    context.ReplaceAll(code_);
+    scope.Close(context);
 }
 
 } }
 
+CYTarget *CYClassExpression::Replace(CYContext &context) {
+    CYBuilder builder;
+
+    CYIdentifier *super(context.Unique());
+
+    CYIdentifier *old(context.super_);
+    context.super_ = super;
+
+    CYIdentifier *constructor(context.Unique());
+    CYForEach (member, tail_->static_)
+        member->Replace(context, builder, $V(constructor), true);
+
+    CYIdentifier *prototype(context.Unique());
+    CYForEach (member, tail_->instance_)
+        member->Replace(context, builder, $V(prototype), true);
+
+    if (tail_->constructor_ == NULL)
+        tail_->constructor_ = $ CYFunctionExpression(NULL, NULL, NULL);
+    tail_->constructor_->name_ = name_;
+    tail_->constructor_ = CYSuperize(context, tail_->constructor_);
+
+    context.super_ = old;
+
+    return $C1($ CYFunctionExpression(NULL, $P($B(super)), $$
+        ->* $ CYVar($B1($B(constructor, tail_->constructor_)))
+        ->* $ CYVar($B1($B(prototype, $ CYFunctionExpression(NULL, NULL, NULL))))
+        ->* $E($ CYAssign($M($V(prototype), $S("prototype")), $M($V(super), $S("prototype"))))
+        ->* $E($ CYAssign($V(prototype), $N($V(prototype))))
+        ->* CYDefineProperty($V(prototype), $S("constructor"), false, false, $ CYPropertyValue($S("value"), $V(constructor)))
+        ->* $ CYVar(builder.bindings_)
+        ->* builder.statements_
+        ->* CYDefineProperty($V(constructor), $S("prototype"), false, false, $ CYPropertyValue($S("value"), $V(prototype)))
+        ->* $ CYReturn($V(constructor))
+    ), tail_->extends_ ?: $V($I("Object")));
+}
+
+CYStatement *CYClassStatement::Replace(CYContext &context) {
+    return $ CYVar($B1($B(name_, $ CYClassExpression(name_, tail_))));
+}
+
 void CYClause::Replace(CYContext &context) { $T()
-    context.Replace(case_);
-    context.ReplaceAll(statements_);
+    context.Replace(value_);
+    context.ReplaceAll(code_);
     next_->Replace(context);
 }
 
-CYStatement *CYComment::Replace(CYContext &context) {
+CYExpression *CYCompound::Replace(CYContext &context) {
+    context.Replace(expression_);
+    context.Replace(next_);
+
+    if (CYCompound *compound = dynamic_cast<CYCompound *>(expression_)) {
+        expression_ = compound->expression_;
+        compound->expression_ = compound->next_;
+        compound->next_ = next_;
+        next_ = compound;
+    }
+
     return this;
 }
 
-CYExpression *CYCompound::Replace(CYContext &context) {
-    context.ReplaceAll(expressions_);
-    if (expressions_ == NULL)
+CYFunctionParameter *CYCompound::Parameter() const {
+    CYFunctionParameter *next(next_->Parameter());
+    if (next == NULL)
         return NULL;
-    return this;
-}
 
-CYExpression *CYCompound::Primitive(CYContext &context) {
-    CYExpression *expression(expressions_);
-    if (expression == NULL)
+    CYFunctionParameter *parameter(expression_->Parameter());
+    if (parameter == NULL)
         return NULL;
-    while (expression->next_ != NULL)
-        expression = expression->next_;
-    return expression->Primitive(context);
+
+    parameter->SetNext(next);
+    return parameter;
 }
 
 CYFunctionParameter *CYComprehension::Parameters(CYContext &context) const { $T(NULL)
@@ -177,6 +250,10 @@ CYStatement *CYComprehension::Replace(CYContext &context, CYStatement *statement
     return next_ == NULL ? statement : next_->Replace(context, statement);
 }
 
+CYExpression *CYComputed::PropertyName(CYContext &context) {
+    return expression_;
+}
+
 CYExpression *CYCondition::Replace(CYContext &context) {
     context.Replace(test_);
     context.Replace(true_);
@@ -188,29 +265,29 @@ void CYContext::NonLocal(CYStatement *&statements) {
     CYContext &context(*this);
 
     if (nextlocal_ != NULL && nextlocal_->identifier_ != NULL) {
-        CYIdentifier *cye($I("$cye")->Replace(context));
-        CYIdentifier *unique(nextlocal_->identifier_->Replace(context));
+        CYIdentifier *cye($I("$cye")->Replace(context, CYIdentifierGlobal));
+        CYIdentifier *unique(nextlocal_->identifier_->Replace(context, CYIdentifierGlobal));
 
         CYStatement *declare(
-            $ CYVar($L1($ CYDeclaration(unique, $ CYObject()))));
+            $ CYVar($B1($B(unique, $ CYObject()))));
 
         cy::Syntax::Catch *rescue(
-            $ cy::Syntax::Catch(cye, $$->*
-                $ CYIf($ CYIdentical($M($V(cye), $S("$cyk")), $V(unique)), $$->*
-                    $ CYReturn($M($V(cye), $S("$cyv"))))->*
-                $ cy::Syntax::Throw($V(cye))));
+            $ cy::Syntax::Catch(cye, $$
+                ->* $ CYIf($ CYIdentical($M($V(cye), $S("$cyk")), $V(unique)), $$
+                    ->* $ CYReturn($M($V(cye), $S("$cyv"))))
+                ->* $ cy::Syntax::Throw($V(cye))));
 
         context.Replace(declare);
         rescue->Replace(context);
 
-        statements = $$->*
-            declare->*
-            $ cy::Syntax::Try(statements, rescue, NULL);
+        statements = $$
+            ->* declare
+            ->* $ cy::Syntax::Try(statements, rescue, NULL);
     }
 }
 
 CYIdentifier *CYContext::Unique() {
-    return $ CYIdentifier(apr_psprintf($pool, "$cy%u", unique_++));
+    return $ CYIdentifier($pool.strcat("$cy", $pool.itoa(unique_++), NULL));
 }
 
 CYStatement *CYContinue::Replace(CYContext &context) {
@@ -221,54 +298,42 @@ CYStatement *CYDebugger::Replace(CYContext &context) {
     return this;
 }
 
-CYAssignment *CYDeclaration::Assignment(CYContext &context) {
-    if (initialiser_ == NULL)
-        return NULL;
-
-    CYAssignment *value($ CYAssign(Variable(context), initialiser_));
-    initialiser_ = NULL;
-    return value;
-}
-
-CYVariable *CYDeclaration::Variable(CYContext &context) {
+CYTarget *CYBinding::Target(CYContext &context) {
     return $V(identifier_);
 }
 
-CYStatement *CYDeclaration::ForEachIn(CYContext &context, CYExpression *value) {
-    return $ CYVar($L1($ CYDeclaration(identifier_, value)));
-}
+CYAssignment *CYBinding::Replace(CYContext &context, CYIdentifierKind kind) {
+    identifier_ = identifier_->Replace(context, kind);
 
-CYExpression *CYDeclaration::Replace(CYContext &context) {
-    context.Replace(identifier_);
-    context.scope_->Declare(context, identifier_, CYIdentifierVariable);
-    return Variable(context);
-}
+    if (initializer_ == NULL)
+        return NULL;
 
-void CYDeclarations::Replace(CYContext &context) { $T()
-    declaration_->Replace(context);
-    next_->Replace(context);
+    CYAssignment *value($ CYAssign(Target(context), initializer_));
+    initializer_ = NULL;
+    return value;
 }
 
-CYProperty *CYDeclarations::Property(CYContext &context) { $T(NULL)
-    return $ CYProperty(declaration_->identifier_, declaration_->initialiser_, next_->Property(context));
-}
+CYExpression *CYBindings::Replace(CYContext &context, CYIdentifierKind kind) { $T(NULL)
+    CYAssignment *assignment(binding_->Replace(context, kind));
+    CYExpression *compound(next_->Replace(context, kind));
 
-CYFunctionParameter *CYDeclarations::Parameter(CYContext &context) { $T(NULL)
-    return $ CYFunctionParameter($ CYDeclaration(declaration_->identifier_), next_->Parameter(context));
+    if (assignment != NULL)
+        if (compound == NULL)
+            compound = assignment;
+        else
+            compound = $ CYCompound(assignment, compound);
+    return compound;
 }
 
-CYArgument *CYDeclarations::Argument(CYContext &context) { $T(NULL)
-    return $ CYArgument(declaration_->initialiser_, next_->Argument(context));
+CYFunctionParameter *CYBindings::Parameter(CYContext &context) { $T(NULL)
+    return $ CYFunctionParameter($ CYBinding(binding_->identifier_), next_->Parameter(context));
 }
 
-CYCompound *CYDeclarations::Compound(CYContext &context) { $T(NULL)
-    CYCompound *compound(next_->Compound(context) ?: $ CYCompound());
-    if (CYAssignment *assignment = declaration_->Assignment(context))
-        compound->AddPrev(assignment);
-    return compound;
+CYArgument *CYBindings::Argument(CYContext &context) { $T(NULL)
+    return $ CYArgument(binding_->initializer_, next_->Argument(context));
 }
 
-CYExpression *CYDirectMember::Replace(CYContext &context) {
+CYTarget *CYDirectMember::Replace(CYContext &context) {
     context.Replace(object_);
     context.Replace(property_);
     return this;
@@ -276,50 +341,60 @@ CYExpression *CYDirectMember::Replace(CYContext &context) {
 
 CYStatement *CYDoWhile::Replace(CYContext &context) {
     context.Replace(test_);
-    context.Replace(code_);
+    context.ReplaceAll(code_);
     return this;
 }
 
-void CYElement::Replace(CYContext &context) { $T()
+void CYElementSpread::Replace(CYContext &context) {
     context.Replace(value_);
-    next_->Replace(context);
 }
 
-CYStatement *CYEmpty::Replace(CYContext &context) {
+void CYElementValue::Replace(CYContext &context) {
+    context.Replace(value_);
+}
+
+CYForInitializer *CYEmpty::Replace(CYContext &context) {
     return NULL;
 }
 
-CYStatement *CYExpress::Replace(CYContext &context) {
-    while (CYExpress *express = dynamic_cast<CYExpress *>(next_)) {
-        CYCompound *compound(dynamic_cast<CYCompound *>(express->expression_));
-        if (compound == NULL)
-            compound = $ CYCompound(express->expression_);
-        compound->AddPrev(expression_);
-        expression_ = compound;
-        SetNext(express->next_);
-    }
+CYTarget *CYEncodedType::Replace(CYContext &context) {
+    return typed_->Replace(context);
+}
 
-    context.Replace(expression_);
-    if (expression_ == NULL)
-        return $ CYEmpty();
+CYTarget *CYEval::Replace(CYContext &context) {
+    context.scope_->Damage();
+    if (arguments_ != NULL)
+        arguments_->value_ = $C1($M($V("Cycript"), $S("compile")), arguments_->value_);
+    return $C($V("eval"), arguments_);
+}
+
+CYStatement *CYExpress::Return() {
+    return $ CYReturn(expression_);
+}
 
+CYForInitializer *CYExpress::Replace(CYContext &context) {
+    context.Replace(expression_);
     return this;
 }
 
-CYExpression *CYExpression::AddArgument(CYContext &context, CYExpression *value) {
+CYTarget *CYExpression::AddArgument(CYContext &context, CYExpression *value) {
     return $C1(this, value);
 }
 
-CYExpression *CYExpression::ClassName(CYContext &context, bool object) {
-    return this;
+CYFunctionParameter *CYExpression::Parameter() const {
+    return NULL;
 }
 
-CYStatement *CYExpression::ForEachIn(CYContext &context, CYExpression *value) {
-    return $E($ CYAssign(this, value));
+CYTarget *CYExtend::Replace(CYContext &context) {
+    return object_.Replace(context, lhs_);
 }
 
-CYAssignment *CYExpression::Assignment(CYContext &context) {
-    return NULL;
+CYStatement *CYExternalDefinition::Replace(CYContext &context) {
+    return $E($ CYAssign($V(name_), $ CYExternalExpression(abi_, type_, name_)));
+}
+
+CYTarget *CYExternalExpression::Replace(CYContext &context) {
+    return $C1(type_->Replace(context), $C2($V("dlsym"), $V("RTLD_DEFAULT"), name_->PropertyName(context)));
 }
 
 CYNumber *CYFalse::Number(CYContext &context) {
@@ -330,86 +405,128 @@ CYString *CYFalse::String(CYContext &context) {
     return $S("false");
 }
 
+CYExpression *CYFatArrow::Replace(CYContext &context) {
+    CYFunctionExpression *function($ CYFunctionExpression(NULL, parameters_, code_));
+    function->this_.SetNext(context.this_);
+    return function;
+}
+
 void CYFinally::Replace(CYContext &context) { $T()
-    code_.Replace(context);
+    CYScope scope(true, context);
+    context.ReplaceAll(code_);
+    scope.Close(context);
 }
 
 CYStatement *CYFor::Replace(CYContext &context) {
-    context.Replace(initialiser_);
+    CYScope outer(true, context);
+    context.Replace(initializer_);
+
     context.Replace(test_);
+
+    {
+        CYScope inner(true, context);
+        context.ReplaceAll(code_);
+        inner.Close(context);
+    }
+
     context.Replace(increment_);
-    context.Replace(code_);
+
+    outer.Close(context);
     return this;
 }
 
-CYCompound *CYForDeclarations::Replace(CYContext &context) {
-    declarations_->Replace(context);
-    return declarations_->Compound(context);
+CYStatement *CYForLexical::Initialize(CYContext &context, CYExpression *value) {
+    if (value == NULL) {
+        if (binding_->initializer_ == NULL)
+            return NULL;
+        value = binding_->initializer_;
+    }
+
+    return $ CYLexical(constant_, $B1($ CYBinding(binding_->identifier_, value)));
+}
+
+CYTarget *CYForLexical::Replace(CYContext &context) {
+    _assert(binding_->Replace(context, CYIdentifierLexical) == NULL);
+    return binding_->Target(context);
 }
 
-// XXX: this still feels highly suboptimal
 CYStatement *CYForIn::Replace(CYContext &context) {
-    if (CYAssignment *assignment = initialiser_->Assignment(context))
-        return $ CYBlock($$->*
-            $E(assignment)->*
-            this
-        );
-
-    context.Replace(initialiser_);
-    context.Replace(set_);
-    context.Replace(code_);
+    CYScope scope(true, context);
+    context.Replace(initializer_);
+    context.Replace(iterable_);
+    context.ReplaceAll(code_);
+    scope.Close(context);
     return this;
 }
 
+CYStatement *CYForInitialized::Replace(CYContext &context) {
+    CYAssignment *assignment(binding_->Replace(context, CYIdentifierVariable));
+    return $ CYBlock($$
+        ->* (assignment == NULL ? NULL : $ CYExpress(assignment))
+        ->* $ CYForIn(binding_->Target(context), iterable_, code_));
+}
+
 CYFunctionParameter *CYForInComprehension::Parameter(CYContext &context) const {
-    return $ CYFunctionParameter($ CYDeclaration(name_));
+    return $ CYFunctionParameter(binding_);
 }
 
 CYStatement *CYForInComprehension::Replace(CYContext &context, CYStatement *statement) const {
-    return $ CYForIn($V(name_), set_, CYComprehension::Replace(context, statement));
+    return $ CYForIn(binding_->Target(context), iterable_, CYComprehension::Replace(context, statement));
 }
 
 CYStatement *CYForOf::Replace(CYContext &context) {
-    if (CYAssignment *assignment = initialiser_->Assignment(context))
-        return $ CYBlock($$->*
-            $E(assignment)->*
-            this
-        );
-
-    CYIdentifier *cys($I("$cys")), *cyt($I("$cyt"));
-
-    return $ CYLetStatement($L2($ CYDeclaration(cys, set_), $ CYDeclaration(cyt)), $$->*
-        $ CYForIn($V(cyt), $V(cys), $ CYBlock($$->*
-            initialiser_->ForEachIn(context, $M($V(cys), $V(cyt)))->*
-            code_
-        ))
-    );
+    CYIdentifier *item(context.Unique()), *list(context.Unique());
+
+    return $ CYBlock($$
+        ->* initializer_->Initialize(context, NULL)
+        ->* $ CYLexical(false, $B2($B(list, iterable_), $B(item)))
+        ->* $ CYForIn($V(item), $V(list), $ CYBlock($$
+            ->* initializer_->Initialize(context, $M($V(list), $V(item)))
+            ->* code_
+    )));
 }
 
 CYFunctionParameter *CYForOfComprehension::Parameter(CYContext &context) const {
-    return $ CYFunctionParameter($ CYDeclaration(name_));
+    return $ CYFunctionParameter(binding_);
 }
 
 CYStatement *CYForOfComprehension::Replace(CYContext &context, CYStatement *statement) const {
-    CYIdentifier *cys($I("cys"));
-
-    return $E($C0($F(NULL, $P1($L("$cys")), $$->*
-        $E($ CYAssign($V(cys), set_))->*
-        $ CYForIn($V(name_), $V(cys), $ CYBlock($$->*
-            $E($ CYAssign($V(name_), $M($V(cys), $V(name_))))->*
-            CYComprehension::Replace(context, statement)
-        ))
+    CYIdentifier *cys(context.Unique());
+
+    return $ CYBlock($$
+        ->* $ CYLexical(false, $B1($B(cys, iterable_)))
+        ->* $ CYForIn(binding_->Target(context), $V(cys), $ CYBlock($$
+            ->* $E($ CYAssign(binding_->Target(context), $M($V(cys), binding_->Target(context))))
+            ->* CYComprehension::Replace(context, statement)
     )));
 }
 
-void CYFunction::Inject(CYContext &context) {
-    context.Replace(name_);
-    context.scope_->Declare(context, name_, CYIdentifierOther);
+CYStatement *CYForVariable::Initialize(CYContext &context, CYExpression *value) {
+    if (value == NULL) {
+        if (binding_->initializer_ == NULL)
+            return NULL;
+        value = binding_->initializer_;
+    }
+
+    return $ CYVar($B1($ CYBinding(binding_->identifier_, value)));
+}
+
+CYTarget *CYForVariable::Replace(CYContext &context) {
+    _assert(binding_->Replace(context, CYIdentifierVariable) == NULL);
+    return binding_->Target(context);
 }
 
-void CYFunction::Replace_(CYContext &context, bool outer) {
-    if (outer)
-        Inject(context);
+// XXX: this is evil evil black magic. don't ask, don't tell... don't believe!
+#define MappingSet "0etnirsoalfucdphmgyvbxTwSNECAFjDLkMOIBPqzRH$_WXUVGYKQJZ"
+//#define MappingSet "0abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_"
+
+void CYFunction::Replace(CYContext &context) {
+    CYThisScope *_this(context.this_);
+    context.this_ = &this_;
+    context.this_ = CYGetLast(context.this_);
+
+    CYIdentifier *super(context.super_);
+    context.super_ = super_;
 
     CYNonLocal *nonlocal(context.nonlocal_);
     CYNonLocal *nextlocal(context.nextlocal_);
@@ -424,57 +541,83 @@ void CYFunction::Replace_(CYContext &context, bool outer) {
         context.nextlocal_ = nonlocal_;
     }
 
-    CYScope scope(!localize, context, code_.statements_);
+    CYScope scope(!localize, context);
 
-    if (!outer && name_ != NULL)
-        Inject(context);
+    $I("arguments")->Replace(context, CYIdentifierMagic);
 
     parameters_->Replace(context, code_);
-    code_.Replace(context);
+
+    context.ReplaceAll(code_);
+
+    if (implicit_)
+        CYImplicitReturn(code_);
+
+    if (CYIdentifier *identifier = this_.identifier_) {
+        context.scope_->Declare(context, identifier, CYIdentifierVariable);
+        code_ = $$
+            ->* $E($ CYAssign($V(identifier), $ CYThis()))
+            ->* code_;
+    }
 
     if (localize)
-        context.NonLocal(code_.statements_);
+        context.NonLocal(code_);
 
     context.nextlocal_ = nextlocal;
     context.nonlocal_ = nonlocal;
 
-    scope.Close();
+    context.super_ = super;
+    context.this_ = _this;
+
+    scope.Close(context, code_);
 }
 
-CYExpression *CYFunctionExpression::Replace(CYContext &context) {
-    Replace_(context, false);
+CYTarget *CYFunctionExpression::Replace(CYContext &context) {
+    CYScope scope(false, context);
+    if (name_ != NULL)
+        name_ = name_->Replace(context, CYIdentifierOther);
+
+    CYFunction::Replace(context);
+    scope.Close(context);
     return this;
 }
 
-void CYFunctionParameter::Replace(CYContext &context, CYBlock &code) { $T()
-    CYAssignment *assignment(initialiser_->Assignment(context));
-    context.Replace(initialiser_);
+void CYFunctionParameter::Replace(CYContext &context, CYStatement *&statements) { $T()
+    CYAssignment *assignment(binding_->Replace(context, CYIdentifierArgument));
 
-    next_->Replace(context, code);
+    next_->Replace(context, statements);
 
     if (assignment != NULL)
-        // XXX: this cast is quite incorrect
-        code.AddPrev($ CYIf($ CYIdentical($ CYTypeOf(dynamic_cast<CYExpression *>(initialiser_)), $S("undefined")), $$->*
-            $E(assignment)
-        ));
+        statements = $$
+            ->* $ CYIf($ CYIdentical($ CYTypeOf(binding_->Target(context)), $S("undefined")), $$
+                ->* $E(assignment))
+            ->* statements;
 }
 
 CYStatement *CYFunctionStatement::Replace(CYContext &context) {
-    Replace_(context, true);
+    name_ = name_->Replace(context, CYIdentifierOther);
+    CYFunction::Replace(context);
     return this;
 }
 
-CYIdentifier *CYIdentifier::Replace(CYContext &context) {
-    if (replace_ != NULL && replace_ != this)
-        return replace_->Replace(context);
-    replace_ = context.scope_->Lookup(context, this);
-    return replace_;
+CYIdentifier *CYIdentifier::Replace(CYContext &context, CYIdentifierKind kind) {
+    if (next_ == this)
+        return this;
+    if (next_ != NULL)
+        return next_->Replace(context, kind);
+    next_ = context.scope_->Declare(context, this, kind)->identifier_;
+    return next_;
+}
+
+CYStatement *CYIf::Return() {
+    CYImplicitReturn(true_);
+    CYImplicitReturn(false_);
+    return this;
 }
 
 CYStatement *CYIf::Replace(CYContext &context) {
     context.Replace(test_);
-    context.Replace(true_);
-    context.Replace(false_);
+    context.ReplaceAll(true_);
+    context.ReplaceAll(false_);
     return this;
 }
 
@@ -486,11 +629,36 @@ CYStatement *CYIfComprehension::Replace(CYContext &context, CYStatement *stateme
     return $ CYIf(test_, CYComprehension::Replace(context, statement));
 }
 
-CYExpression *CYIndirect::Replace(CYContext &context) {
+CYStatement *CYImport::Replace(CYContext &context) {
+    return $ CYVar($B1($B($I(module_->part_->Word()), $C1($V("require"), module_->Replace(context, "/")))));
+}
+
+CYStatement *CYImportDeclaration::Replace(CYContext &context) {
+    CYIdentifier *module(context.Unique());
+
+    CYList<CYStatement> statements;
+    CYForEach (specifier, specifiers_)
+        statements->*specifier->Replace(context, module);
+
+    return $ CYBlock($$
+        ->* $ CYLexical(false, $B1($B(module, $C1($V("require"), module_))))
+        ->* statements);
+}
+
+CYStatement *CYImportSpecifier::Replace(CYContext &context, CYIdentifier *module) {
+    binding_ = binding_->Replace(context, CYIdentifierLexical);
+
+    CYExpression *import($V(module));
+    if (name_ != NULL)
+        import = $M(import, $S(name_));
+    return $E($ CYAssign($V(binding_), import));
+}
+
+CYTarget *CYIndirect::Replace(CYContext &context) {
     return $M(rhs_, $S("$cyi"));
 }
 
-CYExpression *CYIndirectMember::Replace(CYContext &context) {
+CYTarget *CYIndirectMember::Replace(CYContext &context) {
     return $M($ CYIndirect(object_), property_);
 }
 
@@ -505,19 +673,49 @@ CYStatement *CYLabel::Replace(CYContext &context) {
     return this;
 }
 
-CYStatement *CYLetStatement::Replace(CYContext &context) {
-    return $E($ CYCall(CYNonLocalize(context, $ CYFunctionExpression(NULL, declarations_->Parameter(context), code_)), declarations_->Argument(context)));
+CYTarget *CYLambda::Replace(CYContext &context) {
+    return $N2($V("Functor"), $ CYFunctionExpression(NULL, parameters_->Parameters(context), code_), parameters_->TypeSignature(context, typed_->Replace(context)));
+}
+
+CYForInitializer *CYLexical::Replace(CYContext &context) {
+    if (CYExpression *expression = bindings_->Replace(context, CYIdentifierLexical))
+        return $E(expression);
+    return $ CYEmpty();
+}
+
+CYFunctionExpression *CYMethod::Constructor() {
+    return NULL;
+}
+
+void CYMethod::Replace(CYContext &context) {
+    CYFunction::Replace(context);
+}
+
+CYString *CYModule::Replace(CYContext &context, const char *separator) const {
+    if (next_ == NULL)
+        return $ CYString(part_);
+    return $ CYString($pool.strcat(next_->Replace(context, separator)->Value(), separator, part_->Word(), NULL));
+}
+
+CYExpression *CYMultiply::Replace(CYContext &context) {
+    CYInfix::Replace(context);
+
+    if (CYNumber *lhn = lhs_->Number(context))
+        if (CYNumber *rhn = rhs_->Number(context))
+            return $D(lhn->Value() * rhn->Value());
+
+    return this;
 }
 
 namespace cy {
 namespace Syntax {
 
-CYExpression *New::AddArgument(CYContext &context, CYExpression *value) {
-    CYSetLast(arguments_, $ CYArgument(value));
+CYTarget *New::AddArgument(CYContext &context, CYExpression *value) {
+    CYSetLast(arguments_) = $ CYArgument(value);
     return this;
 }
 
-CYExpression *New::Replace(CYContext &context) {
+CYTarget *New::Replace(CYContext &context) {
     context.Replace(constructor_);
     arguments_->Replace(context);
     return this;
@@ -539,11 +737,37 @@ CYNumber *CYNumber::Number(CYContext &context) {
 
 CYString *CYNumber::String(CYContext &context) {
     // XXX: there is a precise algorithm for this
-    return $S(apr_psprintf($pool, "%.17g", Value()));
+    return $S($pool.sprintf(24, "%.17g", Value()));
 }
 
-CYExpression *CYObject::Replace(CYContext &context) {
-    properties_->Replace(context);
+CYExpression *CYNumber::PropertyName(CYContext &context) {
+    return String(context);
+}
+
+CYTarget *CYObject::Replace(CYContext &context, CYTarget *seed) {
+    CYBuilder builder;
+    if (properties_ != NULL)
+        properties_ = properties_->ReplaceAll(context, builder, $ CYThis(), seed != this);
+
+    if (builder) {
+        return $C1($M($ CYFunctionExpression(NULL, builder.bindings_->Parameter(context),
+            builder.statements_
+                ->* $ CYReturn($ CYThis())
+        ), $S("call")), seed, builder.bindings_->Argument(context));
+    }
+
+    CYForEach (property, properties_)
+        property->Replace(context);
+    return seed;
+}
+
+CYTarget *CYObject::Replace(CYContext &context) {
+    return Replace(context, this);
+}
+
+CYTarget *CYParenthetical::Replace(CYContext &context) {
+    // XXX: return expression_;
+    context.Replace(expression_);
     return this;
 }
 
@@ -557,59 +781,99 @@ CYExpression *CYPrefix::Replace(CYContext &context) {
     return this;
 }
 
-// XXX: this is evil evil black magic. don't ask, don't tell... don't believe!
-#define MappingSet "0etnirsoalfucdphmgyvbxTwSNECAFjDLkMOIBPqzRH$_WXUVGYKQJZ"
-//#define MappingSet "0abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_"
+CYProperty *CYProperty::ReplaceAll(CYContext &context, CYBuilder &builder, CYExpression *self, bool update) {
+    update |= Update();
+    if (update)
+        Replace(context, builder, self, false);
+    if (next_ != NULL)
+        next_ = next_->ReplaceAll(context, builder, self, update);
+    return update ? next_ : this;
+}
 
-namespace {
-    struct IdentifierUsageLess :
-        std::binary_function<CYIdentifier *, CYIdentifier *, bool>
-    {
-        _finline bool operator ()(CYIdentifier *lhs, CYIdentifier *rhs) const {
-            if (lhs->usage_ != rhs->usage_)
-                return lhs->usage_ > rhs->usage_;
-            return lhs < rhs;
-        }
-    };
+void CYProperty::Replace(CYContext &context, CYBuilder &builder, CYExpression *self, bool protect) {
+    CYExpression *name(name_->PropertyName(context));
+    if (name_->Computed()) {
+        CYIdentifier *unique(context.Unique());
+        builder.bindings_
+            ->* $B1($B(unique, name));
+        name = $V(unique);
+    }
 
-    typedef std::set<CYIdentifier *, IdentifierUsageLess> IdentifierUsages;
+    Replace(context, builder, self, name, protect);
 }
 
-void CYProgram::Replace(CYContext &context) {
-    CYScope scope(true, context, statements_);
+bool CYProperty::Update() const {
+    return name_->Computed();
+}
 
-    context.nextlocal_ = $ CYNonLocal();
-    context.ReplaceAll(statements_);
-    context.NonLocal(statements_);
+void CYPropertyGetter::Replace(CYContext &context, CYBuilder &builder, CYExpression *self, CYExpression *name, bool protect) {
+    CYIdentifier *unique(context.Unique());
+    builder.bindings_
+        ->* $B1($B(unique, CYSuperize(context, $ CYFunctionExpression(NULL, parameters_, code_))));
+    builder.statements_
+        ->* CYDefineProperty(self, name, true, !protect, $ CYPropertyValue($S("get"), $V(unique)));
+}
+
+CYFunctionExpression *CYPropertyMethod::Constructor() {
+    return name_->Constructor() ? $ CYFunctionExpression(NULL, parameters_, code_) : NULL;
+}
+
+void CYPropertyMethod::Replace(CYContext &context, CYBuilder &builder, CYExpression *self, CYExpression *name, bool protect) {
+    CYIdentifier *unique(context.Unique());
+    builder.bindings_
+        ->* $B1($B(unique, CYSuperize(context, $ CYFunctionExpression(NULL, parameters_, code_))));
+    builder.statements_
+        ->* (!protect ? $E($ CYAssign($M(self, name), $V(unique))) :
+            CYDefineProperty(self, name, true, !protect, $ CYPropertyValue($S("value"), $V(unique), $ CYPropertyValue($S("writable"), $ CYTrue()))));
+}
+
+bool CYPropertyMethod::Update() const {
+    return true;
+}
 
-    scope.Close();
+void CYPropertySetter::Replace(CYContext &context, CYBuilder &builder, CYExpression *self, CYExpression *name, bool protect) {
+    CYIdentifier *unique(context.Unique());
+    builder.bindings_
+        ->* $B1($B(unique, CYSuperize(context, $ CYFunctionExpression(NULL, parameters_, code_))));
+    builder.statements_
+        ->* CYDefineProperty(self, name, true, !protect, $ CYPropertyValue($S("set"), $V(unique)));
+}
 
-    size_t offset(0);
+void CYPropertyValue::Replace(CYContext &context, CYBuilder &builder, CYExpression *self, CYExpression *name, bool protect) {
+    _assert(!protect);
+    CYIdentifier *unique(context.Unique());
+    builder.bindings_
+        ->* $B1($B(unique, value_));
+    builder.statements_
+        ->* $E($ CYAssign($M(self, name), $V(unique)));
+}
+
+void CYPropertyValue::Replace(CYContext &context) {
+    context.Replace(value_);
+}
 
-    CYCStringSet external;
-    for (CYIdentifierValueSet::const_iterator i(scope.identifiers_.begin()); i != scope.identifiers_.end(); ++i)
-        external.insert((*i)->Word());
+void CYScript::Replace(CYContext &context) {
+    CYScope scope(false, context);
+    context.scope_->Damage();
 
-    IdentifierUsages usages;
+    context.nextlocal_ = $ CYNonLocal();
+    context.ReplaceAll(code_);
+    context.NonLocal(code_);
 
-    if (offset < context.rename_.size())
-        CYForEach (i, context.rename_[offset].identifier_)
-            usages.insert(i);
+    scope.Close(context, code_);
 
-    // XXX: totalling the probable occurrences and sorting by them would improve the result
-    for (CYIdentifierUsageVector::const_iterator i(context.rename_.begin()); i != context.rename_.end(); ++i, ++offset) {
-        //std::cout << *i << ":" << (*i)->offset_ << std::endl;
+    unsigned offset(0);
 
+    for (std::vector<CYIdentifier *>::const_iterator i(context.replace_.begin()); i != context.replace_.end(); ++i) {
         const char *name;
-
         if (context.options_.verbose_)
-            name = apr_psprintf($pool, "$%"APR_SIZE_T_FMT"", offset);
+            name = $pool.strcat("$", $pool.itoa(offset++), NULL);
         else {
             char id[8];
             id[7] = '\0';
 
           id:
-            unsigned position(7), local(offset + 1);
+            unsigned position(7), local(offset++ + 1);
 
             do {
                 unsigned index(local % (sizeof(MappingSet) - 1));
@@ -617,32 +881,28 @@ void CYProgram::Replace(CYContext &context) {
                 id[--position] = MappingSet[index];
             } while (local != 0);
 
-            if (external.find(id + position) != external.end()) {
-                ++offset;
+            if (scope.Lookup(context, id + position) != NULL)
                 goto id;
-            }
-
-            name = apr_pstrmemdup($pool, id + position, 7 - position);
             // XXX: at some point, this could become a keyword
+
+            name = $pool.strmemdup(id + position, 7 - position);
         }
 
-        CYForEach (identifier, i->identifier_)
-            identifier->Set(name);
+        CYIdentifier *identifier(*i);
+        _assert(identifier->next_ == identifier);
+        identifier->next_ = $I(name);
     }
 }
 
-void CYProperty::Replace(CYContext &context) { $T()
-    context.Replace(value_);
-    next_->Replace(context);
-    if (value_ == NULL)
-        value_ = $U;
+CYTarget *CYResolveMember::Replace(CYContext &context) {
+    return $M($M(object_, $S("$cyr")), property_);
 }
 
 CYStatement *CYReturn::Replace(CYContext &context) {
     if (context.nonlocal_ != NULL) {
-        CYProperty *value(value_ == NULL ? NULL : $ CYProperty($S("$cyv"), value_));
+        CYProperty *value(value_ == NULL ? NULL : $ CYPropertyValue($S("$cyv"), value_));
         return $ cy::Syntax::Throw($ CYObject(
-            $ CYProperty($S("$cyk"), $V(context.nonlocal_->Target(context)), value)
+            $ CYPropertyValue($S("$cyk"), $V(context.nonlocal_->Target(context)), value)
         ));
     }
 
@@ -650,135 +910,183 @@ CYStatement *CYReturn::Replace(CYContext &context) {
     return this;
 }
 
-CYExpression *CYRubyBlock::Replace(CYContext &context) {
-    // XXX: this needs to do something much more epic to handle return
-    return call_->AddArgument(context, proc_->Replace(context));
+CYTarget *CYRubyBlock::Replace(CYContext &context) {
+    return lhs_->AddArgument(context, proc_->Replace(context));
+}
+
+CYTarget *CYRubyBlock::AddArgument(CYContext &context, CYExpression *value) {
+    return Replace(context)->AddArgument(context, value);
 }
 
-CYExpression *CYRubyProc::Replace(CYContext &context) {
-    return CYNonLocalize(context, $ CYFunctionExpression(NULL, parameters_, code_));
+CYTarget *CYRubyProc::Replace(CYContext &context) {
+    CYFunctionExpression *function($ CYFunctionExpression(NULL, parameters_, code_));
+    function = CYNonLocalize(context, function);
+    function->implicit_ = true;
+    return function;
 }
 
-CYScope::CYScope(bool transparent, CYContext &context, CYStatement *&statements) :
+CYScope::CYScope(bool transparent, CYContext &context) :
     transparent_(transparent),
-    context_(context),
-    statements_(statements),
-    parent_(context.scope_)
+    parent_(context.scope_),
+    damaged_(false),
+    shadow_(NULL),
+    internal_(NULL)
 {
-    context_.scope_ = this;
+    _assert(!transparent_ || parent_ != NULL);
+    context.scope_ = this;
 }
 
-CYScope::~CYScope() {
+void CYScope::Damage() {
+    damaged_ = true;
+    if (parent_ != NULL)
+        parent_->Damage();
 }
 
-void CYScope::Close() {
-    context_.scope_ = parent_;
-    Scope(context_, statements_);
+CYIdentifierFlags *CYScope::Lookup(CYContext &context, const char *word) {
+    CYForEach (i, internal_)
+        if (strcmp(i->identifier_->Word(), word) == 0)
+            return i;
+    return NULL;
 }
 
-void CYScope::Declare(CYContext &context, CYIdentifier *identifier, CYIdentifierFlags flags) {
-    if (!transparent_ || flags == CYIdentifierArgument || flags == CYIdentifierCatch)
-        internal_.insert(CYIdentifierAddressFlagsMap::value_type(identifier, flags));
-    else if (parent_ != NULL)
-        parent_->Declare(context, identifier, flags);
+CYIdentifierFlags *CYScope::Lookup(CYContext &context, CYIdentifier *identifier) {
+    return Lookup(context, identifier->Word());
+}
+
+CYIdentifierFlags *CYScope::Declare(CYContext &context, CYIdentifier *identifier, CYIdentifierKind kind) {
+    _assert(identifier->next_ == NULL || identifier->next_ == identifier);
+
+    CYIdentifierFlags *existing(Lookup(context, identifier));
+    if (existing == NULL)
+        internal_ = $ CYIdentifierFlags(identifier, kind, internal_);
+    ++internal_->count_;
+    if (existing == NULL)
+        return internal_;
+
+    if (kind == CYIdentifierGlobal);
+    else if (existing->kind_ == CYIdentifierGlobal || existing->kind_ == CYIdentifierMagic)
+        existing->kind_ = kind;
+    else if (existing->kind_ == CYIdentifierLexical || kind == CYIdentifierLexical)
+        _assert(false);
+    else if (transparent_ && existing->kind_ == CYIdentifierArgument && kind == CYIdentifierVariable)
+        _assert(false);
+    // XXX: throw new SyntaxError() instead of these asserts
+
+    return existing;
 }
 
-CYIdentifier *CYScope::Lookup(CYContext &context, CYIdentifier *identifier) {
-    std::pair<CYIdentifierValueSet::iterator, bool> insert(identifiers_.insert(identifier));
-    return *insert.first;
+void CYScope::Merge(CYContext &context, const CYIdentifierFlags *flags) {
+    _assert(flags->identifier_->next_ == flags->identifier_);
+    CYIdentifierFlags *existing(Declare(context, flags->identifier_, flags->kind_));
+    flags->identifier_->next_ = existing->identifier_;
+
+    existing->count_ += flags->count_;
+    if (existing->offset_ < flags->offset_)
+        existing->offset_ = flags->offset_;
 }
 
-void CYScope::Merge(CYContext &context, CYIdentifier *identifier) {
-    std::pair<CYIdentifierValueSet::iterator, bool> insert(identifiers_.insert(identifier));
-    if (!insert.second) {
-        if ((*insert.first)->offset_ < identifier->offset_)
-            (*insert.first)->offset_ = identifier->offset_;
-        identifier->replace_ = *insert.first;
-        (*insert.first)->usage_ += identifier->usage_ + 1;
+void CYScope::Close(CYContext &context, CYStatement *&statements) {
+    Close(context);
+
+    CYList<CYBindings> bindings;
+
+    CYForEach (i, internal_)
+        if (i->kind_ == CYIdentifierVariable)
+            bindings
+                ->* $ CYBindings($ CYBinding(i->identifier_));
+
+    if (bindings) {
+        CYVar *var($ CYVar(bindings));
+        var->SetNext(statements);
+        statements = var;
     }
 }
 
-namespace {
-    struct IdentifierOffset {
-        size_t offset_;
-        CYIdentifierFlags flags_;
-        size_t usage_;
-        CYIdentifier *identifier_;
+void CYScope::Close(CYContext &context) {
+    context.scope_ = parent_;
 
-        IdentifierOffset(CYIdentifier *identifier, CYIdentifierFlags flags) :
-            offset_(identifier->offset_),
-            flags_(flags),
-            usage_(identifier->usage_),
-            identifier_(identifier)
-        {
-        }
-    };
+    CYForEach (i, internal_) {
+        _assert(i->identifier_->next_ == i->identifier_);
+    switch (i->kind_) {
+        case CYIdentifierLexical: {
+            if (!damaged_) {
+                CYIdentifier *replace(context.Unique());
+                replace->next_ = replace;
+                i->identifier_->next_ = replace;
+                i->identifier_ = replace;
+            }
 
-    struct IdentifierOffsetLess :
-        std::binary_function<const IdentifierOffset &, const IdentifierOffset &, bool>
-    {
-        _finline bool operator ()(const IdentifierOffset &lhs, const IdentifierOffset &rhs) const {
-            if (lhs.offset_ != rhs.offset_)
-                return lhs.offset_ < rhs.offset_;
-            if (lhs.flags_ != rhs.flags_)
-                return lhs.flags_ < rhs.flags_;
-            /*if (lhs.usage_ != rhs.usage_)
-                return lhs.usage_ < rhs.usage_;*/
-            return lhs.identifier_ < rhs.identifier_;
-        }
-    };
+            if (!transparent_)
+                i->kind_ = CYIdentifierVariable;
+            else
+                parent_->Declare(context, i->identifier_, CYIdentifierVariable);
+        } break;
 
-    typedef std::set<IdentifierOffset, IdentifierOffsetLess> IdentifierOffsets;
-}
+        case CYIdentifierVariable: {
+            if (transparent_) {
+                parent_->Declare(context, i->identifier_, i->kind_);
+                i->kind_ = CYIdentifierGlobal;
+            }
+        } break;
+    default:; } }
 
-void CYScope::Scope(CYContext &context, CYStatement *&statements) {
-    if (parent_ == NULL)
+    if (damaged_)
         return;
 
-    CYDeclarations *last(NULL), *curr(NULL);
+    typedef std::multimap<unsigned, CYIdentifier *> CYIdentifierOffsetMap;
+    CYIdentifierOffsetMap offsets;
 
-    IdentifierOffsets offsets;
+    CYForEach (i, internal_) {
+        _assert(i->identifier_->next_ == i->identifier_);
+    switch (i->kind_) {
+        case CYIdentifierArgument:
+        case CYIdentifierVariable:
+            offsets.insert(CYIdentifierOffsetMap::value_type(i->offset_, i->identifier_));
+        break;
+    default:; } }
 
-    for (CYIdentifierAddressFlagsMap::const_iterator i(internal_.begin()); i != internal_.end(); ++i)
-        if (i->second != CYIdentifierMagic)
-            offsets.insert(IdentifierOffset(i->first, i->second));
+    unsigned offset(0);
 
-    size_t offset(0);
+    for (CYIdentifierOffsetMap::const_iterator i(offsets.begin()); i != offsets.end(); ++i) {
+        if (offset < i->first)
+            offset = i->first;
+        CYIdentifier *identifier(i->second);
 
-    for (IdentifierOffsets::const_iterator i(offsets.begin()); i != offsets.end(); ++i) {
-        if (i->flags_ == CYIdentifierVariable) {
-            CYDeclarations *next($ CYDeclarations($ CYDeclaration(i->identifier_)));
-            if (last == NULL)
-                last = next;
-            if (curr != NULL)
-                curr->SetNext(next);
-            curr = next;
+        if (offset >= context.replace_.size())
+            context.replace_.resize(offset + 1, NULL);
+        CYIdentifier *&replace(context.replace_[offset++]);
+
+        if (replace == NULL)
+            replace = identifier;
+        else {
+            _assert(replace->next_ == replace);
+            identifier->next_ = replace;
         }
+    }
+
+    if (parent_ == NULL)
+        return;
 
-        if (offset < i->offset_)
-            offset = i->offset_;
-        if (context.rename_.size() <= offset)
-            context.rename_.resize(offset + 1);
+    CYForEach (i, internal_) {
+    switch (i->kind_) {
+        case CYIdentifierGlobal: {
+            if (i->offset_ < offset)
+                i->offset_ = offset;
+            parent_->Merge(context, i);
+        } break;
+    default:; } }
+}
 
-        CYIdentifierUsage &rename(context.rename_[offset++]);
-        i->identifier_->SetNext(rename.identifier_);
-        rename.identifier_ = i->identifier_;
-        rename.usage_ += i->identifier_->usage_ + 1;
-    }
+CYTarget *CYSubscriptMember::Replace(CYContext &context) {
+    return $C1($M(object_, $S("$cyg")), property_);
+}
 
-    if (last != NULL) {
-        CYVar *var($ CYVar(last));
-        var->SetNext(statements);
-        statements = var;
-    }
+CYElementValue *CYSpan::Replace(CYContext &context) { $T(NULL)
+    return $ CYElementValue(expression_, $ CYElementValue(string_, next_->Replace(context)));
+}
 
-    for (CYIdentifierValueSet::const_iterator i(identifiers_.begin()); i != identifiers_.end(); ++i)
-        if (internal_.find(*i) == internal_.end()) {
-            //std::cout << *i << '=' << offset << std::endl;
-            if ((*i)->offset_ < offset)
-                (*i)->offset_ = offset;
-            parent_->Merge(context, *i);
-        }
+CYStatement *CYStatement::Return() {
+    return this;
 }
 
 CYString *CYString::Concat(CYContext &context, CYString *rhs) const {
@@ -790,22 +1098,81 @@ CYString *CYString::Concat(CYContext &context, CYString *rhs) const {
     return $S(value, size);
 }
 
+CYIdentifier *CYString::Identifier() const {
+    if (const char *word = Word())
+        return $ CYIdentifier(word);
+    return NULL;
+}
+
 CYNumber *CYString::Number(CYContext &context) {
     // XXX: there is a precise algorithm for this
     return NULL;
 }
 
+CYExpression *CYString::PropertyName(CYContext &context) {
+    return this;
+}
+
 CYString *CYString::String(CYContext &context) {
     return this;
 }
 
+CYStatement *CYStructDefinition::Replace(CYContext &context) {
+    CYTarget *target(tail_->Replace(context));
+    if (name_ != NULL)
+        target = $C1($M(target, $S("withName")), $S(name_->Word()));
+    return $ CYLexical(false, $B1($B($I($pool.strcat(name_->Word(), "$cy", NULL)), target)));
+}
+
+CYTarget *CYStructTail::Replace(CYContext &context) {
+    CYList<CYElementValue> types;
+    CYList<CYElementValue> names;
+
+    CYForEach (field, fields_) {
+        types->*$ CYElementValue(field->type_->Replace(context));
+
+        CYExpression *name;
+        if (field->name_ == NULL)
+            name = NULL;
+        else
+            name = field->name_->PropertyName(context);
+        names->*$ CYElementValue(name);
+    }
+
+    return $N2($V("Type"), $ CYArray(types), $ CYArray(names));
+}
+
+CYTarget *CYSuperAccess::Replace(CYContext &context) {
+    return $C1($M($M($M($V(context.super_), $S("prototype")), property_), $S("bind")), $ CYThis());
+}
+
+CYTarget *CYSuperCall::Replace(CYContext &context) {
+    return $C($C1($M($V(context.super_), $S("bind")), $ CYThis()), arguments_);
+}
+
+CYTarget *CYSymbol::Replace(CYContext &context) {
+    return $C1($M($V("Symbol"), $S("for")), $S(name_));
+}
+
 CYStatement *CYSwitch::Replace(CYContext &context) {
     context.Replace(value_);
     clauses_->Replace(context);
     return this;
 }
 
-CYExpression *CYThis::Replace(CYContext &context) {
+CYStatement *CYTarget::Initialize(CYContext &context, CYExpression *value) {
+    if (value == NULL)
+        return NULL;
+    return $E($ CYAssign(this, value));
+}
+
+CYTarget *CYTemplate::Replace(CYContext &context) {
+    return $C2($M($M($M($V("String"), $S("prototype")), $S("concat")), $S("apply")), $S(""), $ CYArray($ CYElementValue(string_, spans_->Replace(context))));
+}
+
+CYTarget *CYThis::Replace(CYContext &context) {
+    if (context.this_ != NULL)
+        return $V(context.this_->Identifier(context));
     return this;
 }
 
@@ -819,7 +1186,7 @@ CYStatement *Throw::Replace(CYContext &context) {
 
 } }
 
-CYExpression *CYTrivial::Replace(CYContext &context) {
+CYTarget *CYTrivial::Replace(CYContext &context) {
     return this;
 }
 
@@ -835,7 +1202,10 @@ namespace cy {
 namespace Syntax {
 
 CYStatement *Try::Replace(CYContext &context) {
-    code_.Replace(context);
+    CYScope scope(true, context);
+    context.ReplaceAll(code_);
+    scope.Close(context);
+
     catch_->Replace(context);
     finally_->Replace(context);
     return this;
@@ -843,32 +1213,171 @@ CYStatement *Try::Replace(CYContext &context) {
 
 } }
 
-CYStatement *CYVar::Replace(CYContext &context) {
-    declarations_->Replace(context);
-    return $E(declarations_->Compound(context));
+CYTarget *CYTypeArrayOf::Replace_(CYContext &context, CYTarget *type) {
+    return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("arrayOf")), $ CYArgument(size_)));
+}
+
+CYTarget *CYTypeBlockWith::Replace_(CYContext &context, CYTarget *type) {
+    return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("blockWith")), parameters_->Argument(context)));
 }
 
-CYExpression *CYVariable::Replace(CYContext &context) {
-    context.Replace(name_);
+CYTarget *CYTypeCharacter::Replace(CYContext &context) {
+    switch (signing_) {
+        case CYTypeNeutral: return $V("char");
+        case CYTypeSigned: return $V("schar");
+        case CYTypeUnsigned: return $V("uchar");
+        default: _assert(false);
+    }
+}
+
+CYTarget *CYTypeConstant::Replace_(CYContext &context, CYTarget *type) {
+    return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("constant"))));
+}
+
+CYStatement *CYTypeDefinition::Replace(CYContext &context) {
+    return $ CYLexical(false, $B1($B(name_, $ CYTypeExpression(type_))));
+}
+
+CYTarget *CYTypeEnum::Replace(CYContext &context) {
+    CYList<CYProperty> properties;
+    CYForEach (constant, constants_)
+        properties->*$ CYPropertyValue($S(constant->name_->Word()), constant->value_);
+    CYObject *constants($ CYObject(properties));
+
+    if (specifier_ == NULL)
+        return $N1($V("Type"), constants);
+    else
+        return $C1($M(specifier_->Replace(context), $S("enumFor")), constants);
+}
+
+CYTarget *CYTypeError::Replace(CYContext &context) {
+    _assert(false);
+    return NULL;
+}
+
+CYTarget *CYTypeExpression::Replace(CYContext &context) {
+    return typed_->Replace(context);
+}
+
+CYTarget *CYTypeInt128::Replace(CYContext &context) {
+    return $V(signing_ == CYTypeUnsigned ? "uint128" : "int128");
+}
+
+CYTarget *CYTypeIntegral::Replace(CYContext &context) {
+    bool u(signing_ == CYTypeUnsigned);
+    switch (length_) {
+        case 0: return $V(u ? "ushort" : "short");
+        case 1: return $V(u ? "uint" : "int");
+        case 2: return $V(u ? "ulong" : "long");
+        case 3: return $V(u ? "ulonglong" : "longlong");
+        default: _assert(false);
+    }
+}
+
+CYTarget *CYTypeModifier::Replace(CYContext &context, CYTarget *type) { $T(type)
+    return Replace_(context, type);
+}
+
+CYTarget *CYTypeFunctionWith::Replace_(CYContext &context, CYTarget *type) {
+    CYList<CYArgument> arguments(parameters_->Argument(context));
+    if (variadic_)
+        arguments->*$C_($ CYNull());
+    return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("functionWith")), arguments));
+}
+
+CYTarget *CYTypePointerTo::Replace_(CYContext &context, CYTarget *type) {
+    return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("pointerTo"))));
+}
+
+CYTarget *CYTypeReference::Replace(CYContext &context) {
+    const char *prefix;
+    switch (kind_) {
+        case CYTypeReferenceStruct: prefix = "$cys"; break;
+        case CYTypeReferenceEnum: prefix = "$cye"; break;
+        default: _assert(false);
+    }
+
+    return $V($pool.strcat(prefix, name_->Word(), NULL));
+}
+
+CYTarget *CYTypeStruct::Replace(CYContext &context) {
+    CYTarget *target(tail_->Replace(context));
+    if (name_ != NULL)
+        target = $C1($M(target, $S("withName")), $S(name_->Word()));
+    return target;
+}
+
+CYTarget *CYTypeVariable::Replace(CYContext &context) {
+    return $V(name_);
+}
+
+CYTarget *CYTypeVoid::Replace(CYContext &context) {
+    return $N1($V("Type"), $ CYString("v"));
+}
+
+CYTarget *CYTypeVolatile::Replace_(CYContext &context, CYTarget *type) {
+    return next_->Replace(context, $ CYCall($ CYDirectMember(type, $ CYString("volatile"))));
+}
+
+CYTarget *CYType::Replace(CYContext &context) {
+    return modifier_->Replace(context, specifier_->Replace(context));
+}
+
+CYTypeFunctionWith *CYType::Function() {
+    CYTypeModifier *&modifier(CYGetLast(modifier_));
+    if (modifier == NULL)
+        return NULL;
+
+    CYTypeFunctionWith *function(modifier->Function());
+    if (function == NULL)
+        return NULL;
+
+    modifier = NULL;
+    return function;
+}
+
+CYArgument *CYTypedParameter::Argument(CYContext &context) { $T(NULL)
+    return $ CYArgument(type_->Replace(context), next_->Argument(context));
+}
+
+CYFunctionParameter *CYTypedParameter::Parameters(CYContext &context) { $T(NULL)
+    return $ CYFunctionParameter($ CYBinding(name_ ?: context.Unique()), next_->Parameters(context));
+}
+
+CYExpression *CYTypedParameter::TypeSignature(CYContext &context, CYExpression *prefix) { $T(prefix)
+    return next_->TypeSignature(context, $ CYAdd(prefix, type_->Replace(context)));
+}
+
+CYForInitializer *CYVar::Replace(CYContext &context) {
+    if (CYExpression *expression = bindings_->Replace(context, CYIdentifierVariable))
+        return $E(expression);
+    return $ CYEmpty();
+}
+
+CYTarget *CYVariable::Replace(CYContext &context) {
+    name_ = name_->Replace(context, CYIdentifierGlobal);
     return this;
 }
 
+CYFunctionParameter *CYVariable::Parameter() const {
+    return $ CYFunctionParameter($ CYBinding(name_));
+}
+
 CYStatement *CYWhile::Replace(CYContext &context) {
     context.Replace(test_);
-    context.Replace(code_);
+    context.ReplaceAll(code_);
     return this;
 }
 
 CYStatement *CYWith::Replace(CYContext &context) {
     context.Replace(scope_);
-    context.Replace(code_);
+    CYScope scope(true, context);
+    scope.Damage();
+    context.ReplaceAll(code_);
+    scope.Close(context);
     return this;
 }
 
-CYExpression *CYWord::ClassName(CYContext &context, bool object) {
-    CYString *name($S(this));
-    if (object)
-        return $C1($V("objc_getClass"), name);
-    else
-        return name;
+CYExpression *CYWord::PropertyName(CYContext &context) {
+    return $S(this);
 }