X-Git-Url: https://git.saurik.com/cycript.git/blobdiff_plain/283e7e33dbc363c7bba72e3838b5e0d61c92bf2b..9777bd50251d7e72c44bfbee7fbad2d8df148e47:/Parser.hpp

diff --git a/Parser.hpp b/Parser.hpp
index 1c5c7ab..aad1d47 100644
--- a/Parser.hpp
+++ b/Parser.hpp
@@ -1,96 +1,179 @@
-/* Cycript - Remove Execution Server and Disassembler
- * Copyright (C) 2009  Jay Freeman (saurik)
+/* Cycript - Optimizing JavaScript Compiler/Runtime
+ * Copyright (C) 2009-2010  Jay Freeman (saurik)
 */
 
-/* Modified BSD License {{{ */
+/* GNU Lesser General Public License, Version 3 {{{ */
 /*
- *        Redistribution and use in source and binary
- * forms, with or without modification, are permitted
- * provided that the following conditions are met:
+ * 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.
  *
- * 1. Redistributions of source code must retain the
- *    above copyright notice, this list of conditions
- *    and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the
- *    above copyright notice, this list of conditions
- *    and the following disclaimer in the documentation
- *    and/or other materials provided with the
- *    distribution.
- * 3. The name of the author may not be used to endorse
- *    or promote products derived from this software
- *    without specific prior written permission.
+ * 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.
  *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS''
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
- * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
- * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
- * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
- * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
- * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-*/
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Cycript.  If not, see <http://www.gnu.org/licenses/>.
+**/
 /* }}} */
 
-#ifndef CYPARSER_HPP
-#define CYPARSER_HPP
+#ifndef CYCRIPT_PARSER_HPP
+#define CYCRIPT_PARSER_HPP
+
+#include <iostream>
 
-#include <cstdlib>
 #include <string>
 #include <vector>
+#include <map>
+#include <set>
+
+#include <cstdio>
+#include <cstdlib>
 
 #include "location.hh"
+
+#include "List.hpp"
 #include "Pooling.hpp"
+#include "Options.hpp"
 
-template <typename Type_>
-struct CYNext {
-    Type_ *next_;
+class CYContext;
 
-    CYNext() :
-        next_(NULL)
+struct CYThing {
+    virtual ~CYThing() {
+    }
+
+    virtual void Output(struct CYOutput &out) const = 0;
+};
+
+struct CYOutput {
+    std::ostream &out_;
+    CYOptions &options_;
+    bool pretty_;
+    unsigned indent_;
+    bool right_;
+
+    enum {
+        NoMode,
+        NoLetter,
+        NoPlus,
+        NoHyphen,
+        Terminated
+    } mode_;
+
+    CYOutput(std::ostream &out, CYOptions &options) :
+        out_(out),
+        options_(options),
+        pretty_(false),
+        indent_(0),
+        right_(false),
+        mode_(NoMode)
     {
     }
 
-    CYNext(Type_ *next) :
-        next_(next)
-    {
+    void Check(char value);
+    void Terminate();
+
+    CYOutput &operator <<(char rhs);
+    CYOutput &operator <<(const char *rhs);
+
+    _finline CYOutput &operator <<(const CYThing *rhs) {
+        if (rhs != NULL)
+            rhs->Output(*this);
+        return *this;
     }
 
-    void SetNext(Type_ *next) {
-        next_ = next;
+    _finline CYOutput &operator <<(const CYThing &rhs) {
+        rhs.Output(*this);
+        return *this;
     }
 };
 
-struct CYThing {
-    virtual void Output(std::ostream &out) const = 0;
+struct CYPropertyName {
+    virtual void PropertyName(CYOutput &out) const = 0;
+
+    virtual ~CYPropertyName() {
+    }
 };
 
-_finline std::ostream &operator <<(std::ostream &out, const CYThing &rhs) {
-    rhs.Output(out);
-    return out;
-}
+struct CYExpression;
 
-struct CYSource :
-    CYNext<CYSource>
-{
-    virtual void Show(std::ostream &out) const;
-    virtual void Output(std::ostream &out) const = 0;
-    virtual void Output(std::ostream &out, bool block) const;
+enum CYNeeded {
+    CYNever     = -1,
+    CYSometimes =  0,
+    CYAlways    =  1,
 };
 
-struct CYName :
-    CYThing
+enum CYFlags {
+    CYNoFlags =      0,
+    CYNoBrace =      (1 << 0),
+    CYNoFunction =   (1 << 1),
+    CYNoIn =         (1 << 2),
+    CYNoCall =       (1 << 3),
+    CYNoRightHand =  (1 << 4),
+    CYNoDangle =     (1 << 5),
+    CYNoInteger =    (1 << 6),
+    CYNoBF =         (CYNoBrace | CYNoFunction),
+};
+
+struct CYStatement :
+    CYNext<CYStatement>
 {
-    virtual const char *Name() const = 0;
+    virtual ~CYStatement() {
+    }
+
+    void Single(CYOutput &out, CYFlags flags) const;
+    void Multiple(CYOutput &out, CYFlags flags = CYNoFlags) const;
+
+    virtual CYStatement *Collapse(CYContext &context);
+    virtual CYStatement *Replace(CYContext &context) = 0;
+
+  private:
+    virtual void Output(CYOutput &out, CYFlags flags) const = 0;
+};
+
+struct CYStatements {
+    CYStatement *first_;
+    CYStatement *last_;
+
+    CYStatements() :
+        first_(NULL),
+        last_(NULL)
+    {
+    }
+
+    operator CYStatement *() const {
+        return first_;
+    }
+
+    CYStatements &operator ->*(CYStatement *next) {
+        if (next != NULL)
+            if (first_ == NULL) {
+                first_ = next;
+                last_ = next;
+            } else for (;; last_ = last_->next_)
+                if (last_->next_ == NULL) {
+                    last_->next_ = next;
+                    last_ = next;
+                    break;
+                }
+        return *this;
+    }
+};
+
+struct CYClassName {
+    virtual ~CYClassName() {
+    }
+
+    virtual CYExpression *ClassName(CYContext &context, bool object) = 0;
+    virtual void ClassName(CYOutput &out, bool object) const = 0;
 };
 
 struct CYWord :
-    CYName
+    CYThing,
+    CYPropertyName,
+    CYClassName
 {
     const char *word_;
 
@@ -99,46 +182,238 @@ struct CYWord :
     {
     }
 
-    const char *Value() const {
-        return word_;
+    void Set(const char *value) {
+        word_ = value;
     }
 
-    virtual const char *Name() const {
-        return Value();
-    }
+    virtual const char *Word() const;
+    virtual void Output(CYOutput &out) const;
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYExpression *ClassName(CYContext &context, bool object);
+    virtual void ClassName(CYOutput &out, bool object) const;
+    virtual void PropertyName(CYOutput &out) const;
 };
 
+_finline std::ostream &operator <<(std::ostream &lhs, const CYWord &rhs) {
+    lhs << &rhs << '=';
+    return lhs << rhs.Word();
+}
+
 struct CYIdentifier :
+    CYNext<CYIdentifier>,
     CYWord
 {
+    CYIdentifier *replace_;
+    size_t offset_;
+    size_t usage_;
+
     CYIdentifier(const char *word) :
-        CYWord(word)
+        CYWord(word),
+        replace_(NULL),
+        offset_(0),
+        usage_(0)
+    {
+    }
+
+    virtual const char *Word() const;
+    CYIdentifier *Replace(CYContext &context);
+};
+
+struct CYComment :
+    CYStatement
+{
+    const char *value_;
+
+    CYComment(const char *value) :
+        value_(value)
     {
     }
+
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYLabel :
-    CYNext<CYLabel>
+    CYStatement
+{
+    CYIdentifier *name_;
+    CYStatement *statement_;
+
+    CYLabel(CYIdentifier *name, CYStatement *statement) :
+        name_(name),
+        statement_(statement)
+    {
+    }
+
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
+};
+
+struct CYCStringLess :
+    std::binary_function<const char *, const char *, bool>
+{
+    _finline bool operator ()(const char *lhs, const char *rhs) const {
+        return strcmp(lhs, rhs) < 0;
+    }
+};
+
+struct CYIdentifierValueLess :
+    std::binary_function<CYIdentifier *, CYIdentifier *, bool>
 {
+    _finline bool operator ()(CYIdentifier *lhs, CYIdentifier *rhs) const {
+        return CYCStringLess()(lhs->Word(), rhs->Word());
+    }
+};
+
+enum CYIdentifierFlags {
+    CYIdentifierArgument,
+    CYIdentifierVariable,
+    CYIdentifierOther,
+    CYIdentifierMagic,
+    CYIdentifierCatch,
+};
+
+typedef std::set<const char *, CYCStringLess> CYCStringSet;
+typedef std::set<CYIdentifier *, CYIdentifierValueLess> CYIdentifierValueSet;
+typedef std::map<CYIdentifier *, CYIdentifierFlags> CYIdentifierAddressFlagsMap;
+
+struct CYIdentifierUsage {
     CYIdentifier *identifier_;
+    size_t usage_;
+};
+
+typedef std::vector<CYIdentifierUsage> CYIdentifierUsageVector;
+
+// XXX: strategy pattern, maybe subclass
+enum CYScopeType {
+    CYScopeCatch,
+    CYScopeFunction,
+    CYScopeProgram,
+};
+
+struct CYScope {
+    CYScopeType type_;
+
+    CYContext &context_;
+    CYStatement *&statements_;
+
+    CYScope *parent_;
 
-    CYLabel(CYIdentifier *identifier, CYLabel *next) :
-        CYNext<CYLabel>(next),
-        identifier_(identifier)
+    CYIdentifierAddressFlagsMap internal_;
+    CYIdentifierValueSet identifiers_;
+
+    CYScope(CYScopeType type, CYContext &context, CYStatement *&statements);
+
+    void Close();
+
+    void Declare(CYContext &context, CYIdentifier *identifier, CYIdentifierFlags flags);
+    virtual CYIdentifier *Lookup(CYContext &context, CYIdentifier *identifier);
+    void Merge(CYContext &context, CYIdentifier *identifier);
+    void Scope(CYContext &context, CYStatement *&statements);
+};
+
+struct CYProgram :
+    CYThing
+{
+    CYStatement *statements_;
+
+    CYProgram(CYStatement *statements) :
+        statements_(statements)
     {
     }
+
+    virtual void Replace(CYContext &context);
+    virtual void Output(CYOutput &out) const;
 };
 
-struct CYStatement :
-    CYSource
+struct CYNonLocal;
+
+struct CYContext {
+    CYOptions &options_;
+
+    CYScope *scope_;
+    CYIdentifierUsageVector rename_;
+
+    CYNonLocal *nonlocal_;
+    CYNonLocal *nextlocal_;
+    unsigned unique_;
+
+    CYContext(CYOptions &options) :
+        options_(options),
+        scope_(NULL),
+        nonlocal_(NULL),
+        nextlocal_(NULL),
+        unique_(0)
+    {
+    }
+
+    virtual ~CYContext() {
+    }
+
+    template <typename Type_>
+    void ReplaceAll(Type_ *&values) {
+        Type_ **last(&values);
+        CYForEach (next, values) {
+            Replace(*last = next);
+            last = &(*last)->next_;
+        }
+    }
+
+    template <typename Type_>
+    void Replace(Type_ *&value) {
+        for (;;) if (value == NULL)
+            break;
+        else {
+            Type_ *replace(value->Replace(*this));
+            if (replace != value)
+                value = replace;
+            else break;
+        }
+    }
+
+    void NonLocal(CYStatement *&statements);
+    CYIdentifier *Unique();
+};
+
+struct CYNonLocal {
+    CYIdentifier *identifier_;
+
+    CYNonLocal() :
+        identifier_(NULL)
+    {
+    }
+
+    CYIdentifier *Target(CYContext &context) {
+        if (identifier_ == NULL)
+            identifier_ = context.Unique();
+        return identifier_;
+    }
+};
+
+struct CYBlock :
+    CYStatement,
+    CYThing
 {
-    CYLabel *label_;
+    CYStatement *statements_;
 
-    void AddLabel(CYIdentifier *identifier) {
-        label_ = new CYLabel(identifier, label_);
+    CYBlock(CYStatement *statements) :
+        statements_(statements)
+    {
+    }
+
+    operator CYStatement *() const {
+        return statements_;
     }
+
+    void AddPrev(CYStatement *statement) {
+        CYSetLast(statement, statements_);
+        statements_ = statement;
+    }
+
+    virtual CYStatement *Replace(CYContext &context);
+
+    virtual void Output(CYOutput &out) const;
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 enum CYState {
@@ -149,67 +424,140 @@ enum CYState {
 
 class CYDriver {
   public:
-    CYPool pool_;
-
     CYState state_;
     void *scanner_;
 
     const char *data_;
     size_t size_;
+    FILE *file_;
+
+    bool strict_;
+
+    enum Condition {
+        RegExpCondition,
+        XMLContentCondition,
+        XMLTagCondition,
+    };
 
     std::string filename_;
 
     struct Error {
+        bool warning_;
         cy::location location_;
         std::string message_;
     };
 
     typedef std::vector<Error> Errors;
 
-    CYSource *source_;
+    CYProgram *program_;
     Errors errors_;
 
+    bool auto_;
+
+    struct Context {
+        CYExpression *context_;
+
+        Context(CYExpression *context) :
+            context_(context)
+        {
+        }
+
+        typedef std::vector<CYWord *> Words;
+        Words words_;
+    };
+
+    typedef std::vector<Context> Contexts;
+    Contexts contexts_;
+
+    CYExpression *context_;
+
+    enum Mode {
+        AutoNone,
+        AutoPrimary,
+        AutoDirect,
+        AutoIndirect,
+        AutoMessage
+    } mode_;
+
   private:
     void ScannerInit();
     void ScannerDestroy();
 
   public:
-    CYDriver(const std::string &filename);
+    CYDriver(const std::string &filename = "");
     ~CYDriver();
-};
 
-struct CYPart {
-    virtual void Part(std::ostream &out) const = 0;
-};
+    Condition GetCondition();
+    void SetCondition(Condition condition);
 
-struct CYForInitialiser :
-    CYPart
-{
+    void PushCondition(Condition condition);
+    void PopCondition();
+
+    void Warning(const cy::location &location, const char *message);
 };
 
-struct CYForInInitialiser :
-    CYPart
-{
+struct CYForInitialiser {
+    virtual ~CYForInitialiser() {
+    }
+
+    virtual void For(CYOutput &out) const = 0;
+    virtual CYExpression *Replace(CYContext &context) = 0;
 };
 
-enum CYFlags {
-    CYNoFlags =    0,
-    CYNoBrace =    (1 << 0),
-    CYNoFunction = (1 << 1),
-    CYNoLeader =   (1 << 2),
-    CYNoTrailer =  (1 << 3),
-    CYNoIn =       (1 << 4),
+struct CYForInInitialiser {
+    virtual ~CYForInInitialiser() {
+    }
+
+    virtual void ForIn(CYOutput &out, CYFlags flags) const = 0;
+    virtual const char *ForEachIn() const = 0;
+    virtual CYExpression *ForEachIn(CYContext &out) = 0;
+    virtual CYExpression *Replace(CYContext &context) = 0;
 };
 
+struct CYNumber;
+struct CYString;
+
 struct CYExpression :
     CYNext<CYExpression>,
     CYForInitialiser,
-    CYForInInitialiser
+    CYForInInitialiser,
+    CYClassName,
+    CYThing
 {
     virtual unsigned Precedence() const = 0;
-    virtual void Part(std::ostream &out) const;
-    virtual void Output(std::ostream &out, CYFlags flags) const = 0;
-    void Output(std::ostream &out, unsigned precedence, CYFlags flags) const;
+
+    virtual bool RightHand() const {
+        return true;
+    }
+
+    virtual void For(CYOutput &out) const;
+    virtual void ForIn(CYOutput &out, CYFlags flags) const;
+
+    virtual const char *ForEachIn() const;
+    virtual CYExpression *ForEachIn(CYContext &out);
+
+    virtual CYExpression *AddArgument(CYContext &context, CYExpression *value);
+
+    virtual void Output(CYOutput &out) const;
+    virtual void Output(CYOutput &out, CYFlags flags) const = 0;
+    void Output(CYOutput &out, unsigned precedence, CYFlags flags) const;
+
+    virtual CYExpression *ClassName(CYContext &context, bool object);
+    virtual void ClassName(CYOutput &out, bool object) const;
+
+    virtual CYExpression *Replace(CYContext &context) = 0;
+
+    virtual CYExpression *Primitive(CYContext &context) {
+        return this;
+    }
+
+    virtual CYNumber *Number(CYContext &context) {
+        return NULL;
+    }
+
+    virtual CYString *String(CYContext &context) {
+        return NULL;
+    }
 
     virtual const char *Word() const {
         return NULL;
@@ -222,7 +570,13 @@ struct CYExpression :
     }
 
 #define CYPrecedence(value) \
+    static const unsigned Precedence_ = value; \
     virtual unsigned Precedence() const { \
+        return Precedence_; \
+    }
+
+#define CYRightHand(value) \
+    virtual bool RightHand() const { \
         return value; \
     }
 
@@ -231,65 +585,162 @@ struct CYCompound :
 {
     CYExpression *expressions_;
 
-    CYCompound(CYExpression *expressions) :
+    CYCompound(CYExpression *expressions = NULL) :
         expressions_(expressions)
     {
     }
 
     void AddPrev(CYExpression *expression) {
-        CYExpression *last(expression);
-        while (last->next_ != NULL)
-            last = last->next_;
-        last->SetNext(expressions_);
+        CYSetLast(expression, expressions_);
         expressions_ = expression;
     }
 
     CYPrecedence(17)
 
-    void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
+    void Output(CYOutput &out, CYFlags flags) const;
 };
 
-struct CYLiteral :
-    CYExpression
+struct CYFunctionParameter :
+    CYNext<CYFunctionParameter>,
+    CYThing
 {
-    CYPrecedence(0)
+    CYIdentifier *name_;
+
+    CYFunctionParameter(CYIdentifier *name, CYFunctionParameter *next = NULL) :
+        CYNext<CYFunctionParameter>(next),
+        name_(name)
+    {
+    }
+
+    virtual CYFunctionParameter *Replace(CYContext &context, CYBlock &code);
+    virtual void Output(CYOutput &out) const;
 };
 
-struct CYMagic :
-    CYExpression
+struct CYOptionalFunctionParameter :
+    CYFunctionParameter
 {
-    CYPrecedence(0)
+    CYExpression *initializer_;
+
+    CYOptionalFunctionParameter(CYIdentifier *name, CYExpression *initializer, CYFunctionParameter *next = NULL) :
+        CYFunctionParameter(name, next),
+        initializer_(initializer)
+    {
+    }
+
+    virtual CYFunctionParameter *Replace(CYContext &context, CYBlock &code);
+    virtual void Output(CYOutput &out) const;
 };
 
-struct CYSelectorPart :
-    CYNext<CYSelectorPart>
+struct CYComprehension :
+    CYNext<CYComprehension>,
+    CYThing
 {
-    CYWord *name_;
-    bool value_;
+    virtual const char *Name() const = 0;
 
-    CYSelectorPart(CYWord *name, bool value, CYSelectorPart *next) :
-        CYNext<CYSelectorPart>(next),
+    virtual CYFunctionParameter *Parameter(CYContext &context) const = 0;
+    CYFunctionParameter *Parameters(CYContext &context) const;
+    virtual CYStatement *Replace(CYContext &context, CYStatement *statement) const;
+    virtual void Output(CYOutput &out) const = 0;
+};
+
+struct CYForInComprehension :
+    CYComprehension
+{
+    CYIdentifier *name_;
+    CYExpression *set_;
+
+    CYForInComprehension(CYIdentifier *name, CYExpression *set) :
         name_(name),
-        value_(value)
+        set_(set)
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual const char *Name() const {
+        return name_->Word();
+    }
+
+    virtual CYFunctionParameter *Parameter(CYContext &context) const;
+    virtual CYStatement *Replace(CYContext &context, CYStatement *statement) const;
+    virtual void Output(CYOutput &out) const;
 };
 
-struct CYSelector :
-    CYLiteral
+struct CYForEachInComprehension :
+    CYComprehension
 {
-    CYSelectorPart *name_;
+    CYIdentifier *name_;
+    CYExpression *set_;
 
-    CYSelector(CYSelectorPart *name) :
-        name_(name)
+    CYForEachInComprehension(CYIdentifier *name, CYExpression *set) :
+        name_(name),
+        set_(set)
     {
     }
 
-    CYPrecedence(1)
+    virtual const char *Name() const {
+        return name_->Word();
+    }
+
+    virtual CYFunctionParameter *Parameter(CYContext &context) const;
+    virtual CYStatement *Replace(CYContext &context, CYStatement *statement) const;
+    virtual void Output(CYOutput &out) const;
+};
+
+struct CYIfComprehension :
+    CYComprehension
+{
+    CYExpression *test_;
+
+    CYIfComprehension(CYExpression *test) :
+        test_(test)
+    {
+    }
+
+    virtual const char *Name() const {
+        return NULL;
+    }
+
+    virtual CYFunctionParameter *Parameter(CYContext &context) const;
+    virtual CYStatement *Replace(CYContext &context, CYStatement *statement) const;
+    virtual void Output(CYOutput &out) const;
+};
+
+struct CYArrayComprehension :
+    CYExpression
+{
+    CYExpression *expression_;
+    CYComprehension *comprehensions_;
+
+    CYArrayComprehension(CYExpression *expression, CYComprehension *comprehensions) :
+        expression_(expression),
+        comprehensions_(comprehensions)
+    {
+    }
+
+    CYPrecedence(0)
+
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
+};
+
+struct CYLiteral :
+    CYExpression
+{
+    CYPrecedence(0)
+    CYRightHand(false)
+};
+
+struct CYTrivial :
+    CYLiteral
+{
+    virtual CYExpression *Replace(CYContext &context);
+};
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+struct CYMagic :
+    CYExpression
+{
+    CYPrecedence(0)
+    CYRightHand(false)
 };
 
 struct CYRange {
@@ -317,20 +768,32 @@ extern CYRange WordStartRange_;
 extern CYRange WordEndRange_;
 
 struct CYString :
-    CYLiteral,
-    CYName
+    CYTrivial,
+    CYPropertyName
 {
     const char *value_;
     size_t size_;
 
+    CYString() :
+        value_(NULL),
+        size_(0)
+    {
+    }
+
+    CYString(const char *value) :
+        value_(value),
+        size_(strlen(value))
+    {
+    }
+
     CYString(const char *value, size_t size) :
         value_(value),
         size_(size)
     {
     }
 
-    CYString(const CYIdentifier *identifier) :
-        value_(identifier->Value()),
+    CYString(const CYWord *word) :
+        value_(word->Word()),
         size_(strlen(value_))
     {
     }
@@ -339,29 +802,19 @@ struct CYString :
         return value_;
     }
 
-    virtual const char *Name() const {
-        return Value();
-    }
-
-    virtual const char *Word() const {
-        if (size_ == 0 || !WordStartRange_[value_[0]])
-            return NULL;
-        for (size_t i(1); i != size_; ++i)
-            if (!WordEndRange_[value_[i]])
-                return NULL;
-        return Value();
-    }
+    virtual const char *Word() const;
 
-    virtual void Output(std::ostream &out) const {
-        return Output(out, CYNoFlags);
-    }
+    virtual CYNumber *Number(CYContext &context);
+    virtual CYString *String(CYContext &context);
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    CYString *Concat(CYContext &out, CYString *rhs) const;
+    virtual void Output(CYOutput &out, CYFlags flags) const;
+    virtual void PropertyName(CYOutput &out) const;
 };
 
 struct CYNumber :
-    CYLiteral,
-    CYName
+    CYTrivial,
+    CYPropertyName
 {
     double value_;
 
@@ -374,27 +827,43 @@ struct CYNumber :
         return value_;
     }
 
-    virtual const char *Name() const {
-        throw;
+    virtual CYNumber *Number(CYContext &context);
+    virtual CYString *String(CYContext &context);
+
+    virtual void Output(CYOutput &out, CYFlags flags) const;
+    virtual void PropertyName(CYOutput &out) const;
+};
+
+struct CYRegEx :
+    CYTrivial
+{
+    const char *value_;
+
+    CYRegEx(const char *value) :
+        value_(value)
+    {
     }
 
-    virtual void Output(std::ostream &out) const {
-        return Output(out, CYNoFlags);
+    const char *Value() const {
+        return value_;
     }
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYNull :
     CYWord,
-    CYLiteral
+    CYTrivial
 {
     CYNull() :
         CYWord("null")
     {
     }
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYNumber *Number(CYContext &context);
+    virtual CYString *String(CYContext &context);
+
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYThis :
@@ -406,14 +875,15 @@ struct CYThis :
     {
     }
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYBoolean :
-    CYLiteral
+    CYTrivial
 {
     virtual bool Value() const = 0;
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYFalse :
@@ -425,7 +895,12 @@ struct CYFalse :
     {
     }
 
-    virtual bool Value() const;
+    virtual bool Value() const {
+        return false;
+    }
+
+    virtual CYNumber *Number(CYContext &context);
+    virtual CYString *String(CYContext &context);
 };
 
 struct CYTrue :
@@ -437,7 +912,12 @@ struct CYTrue :
     {
     }
 
-    virtual bool Value() const;
+    virtual bool Value() const {
+        return true;
+    }
+
+    virtual CYNumber *Number(CYContext &context);
+    virtual CYString *String(CYContext &context);
 };
 
 struct CYVariable :
@@ -450,9 +930,16 @@ struct CYVariable :
     {
     }
 
+    CYVariable(const char *name) :
+        name_(new($pool) CYIdentifier(name))
+    {
+    }
+
     CYPrecedence(0)
+    CYRightHand(false)
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYPrefix :
@@ -468,7 +955,10 @@ struct CYPrefix :
     virtual bool Alphabetic() const = 0;
     virtual const char *Operator() const = 0;
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    CYPrecedence(4)
+
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYInfix :
@@ -483,10 +973,15 @@ struct CYInfix :
     {
     }
 
+    void SetLeft(CYExpression *lhs) {
+        lhs_ = lhs;
+    }
+
     virtual bool Alphabetic() const = 0;
     virtual const char *Operator() const = 0;
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYPostfix :
@@ -501,7 +996,10 @@ struct CYPostfix :
 
     virtual const char *Operator() const = 0;
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    CYPrecedence(3)
+
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYAssignment :
@@ -516,17 +1014,32 @@ struct CYAssignment :
     {
     }
 
+    void SetLeft(CYExpression *lhs) {
+        lhs_ = lhs;
+    }
+
     virtual const char *Operator() const = 0;
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    CYPrecedence(16)
+
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYArgument :
-    CYNext<CYArgument>
+    CYNext<CYArgument>,
+    CYThing
 {
     CYWord *name_;
     CYExpression *value_;
 
+    CYArgument(CYExpression *value, CYArgument *next = NULL) :
+        CYNext<CYArgument>(next),
+        name_(NULL),
+        value_(value)
+    {
+    }
+
     CYArgument(CYWord *name, CYExpression *value, CYArgument *next = NULL) :
         CYNext<CYArgument>(next),
         name_(name),
@@ -534,7 +1047,8 @@ struct CYArgument :
     {
     }
 
-    void Output(std::ostream &out) const;
+    void Replace(CYContext &context);
+    void Output(CYOutput &out) const;
 };
 
 struct CYBlank :
@@ -551,19 +1065,21 @@ struct CYClause :
     CYNext<CYClause>
 {
     CYExpression *case_;
-    CYStatement *code_;
+    CYStatement *statements_;
 
-    CYClause(CYExpression *_case, CYStatement *code) :
+    CYClause(CYExpression *_case, CYStatement *statements) :
         case_(_case),
-        code_(code)
+        statements_(statements)
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    void Replace(CYContext &context);
+    virtual void Output(CYOutput &out) const;
 };
 
 struct CYElement :
-    CYNext<CYElement>
+    CYNext<CYElement>,
+    CYThing
 {
     CYExpression *value_;
 
@@ -573,7 +1089,8 @@ struct CYElement :
     {
     }
 
-    void Output(std::ostream &out) const;
+    void Replace(CYContext &context);
+    void Output(CYOutput &out) const;
 };
 
 struct CYArray :
@@ -581,120 +1098,106 @@ struct CYArray :
 {
     CYElement *elements_;
 
-    CYArray(CYElement *elements) :
+    CYArray(CYElement *elements = NULL) :
         elements_(elements)
     {
     }
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
+};
+
+struct CYProperty :
+    CYNext<CYProperty>,
+    CYThing
+{
+    CYPropertyName *name_;
+    CYExpression *value_;
+
+    CYProperty(CYPropertyName *name, CYExpression *value, CYProperty *next = NULL) :
+        CYNext<CYProperty>(next),
+        name_(name),
+        value_(value)
+    {
+    }
+
+    void Replace(CYContext &context);
+    virtual void Output(CYOutput &out) const;
 };
 
 struct CYDeclaration :
-    CYThing,
     CYForInInitialiser
 {
     CYIdentifier *identifier_;
     CYExpression *initialiser_;
 
-    CYDeclaration(CYIdentifier *identifier, CYExpression *initialiser) :
+    CYDeclaration(CYIdentifier *identifier, CYExpression *initialiser = NULL) :
         identifier_(identifier),
         initialiser_(initialiser)
     {
     }
 
-    virtual void Part(std::ostream &out) const;
-    virtual void Output(std::ostream &out) const;
+    virtual void ForIn(CYOutput &out, CYFlags flags) const;
+
+    virtual const char *ForEachIn() const;
+    virtual CYExpression *ForEachIn(CYContext &out);
+
+    virtual CYExpression *Replace(CYContext &context);
+    virtual CYAssignment *Assignment(CYContext &context);
+
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYDeclarations :
-    CYStatement,
+    CYNext<CYDeclarations>,
+    CYThing,
     CYForInitialiser
 {
     CYDeclaration *declaration_;
-    CYDeclarations *next_;
 
-    CYDeclarations(CYDeclaration *declaration, CYDeclarations *next) :
-        declaration_(declaration),
-        next_(next)
+    CYDeclarations(CYDeclaration *declaration, CYDeclarations *next = NULL) :
+        CYNext<CYDeclarations>(next),
+        declaration_(declaration)
     {
     }
 
-    virtual void Part(std::ostream &out) const;
-    virtual void Output(std::ostream &out) const;
-};
-
-struct CYField :
-    CYNext<CYField>
-{
-    virtual void Output(std::ostream &out) const;
-};
+    virtual void For(CYOutput &out) const;
 
-struct CYMessageParameter :
-    CYNext<CYMessageParameter>
-{
-    CYWord *tag_;
-    CYExpression *type_;
-    CYIdentifier *name_;
+    virtual CYCompound *Replace(CYContext &context);
+    CYProperty *Property(CYContext &context);
 
-    CYMessageParameter(CYWord *tag, CYExpression *type, CYIdentifier *name) :
-        tag_(tag),
-        type_(type),
-        name_(name)
-    {
-    }
+    virtual void Output(CYOutput &out) const;
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
-struct CYMessage :
-    CYSource
+struct CYVar :
+    CYStatement
 {
-    bool instance_;
-    CYExpression *type_;
-    CYMessageParameter *parameter_;
-    CYSource *body_;
+    CYDeclarations *declarations_;
 
-    CYMessage(bool instance, CYExpression *type, CYMessageParameter *parameter, CYSource *body) :
-        instance_(instance),
-        type_(type),
-        parameter_(parameter),
-        body_(body)
+    CYVar(CYDeclarations *declarations) :
+        declarations_(declarations)
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
-struct CYClass :
-    CYSource
-{
-    CYIdentifier *name_;
-    CYExpression *super_;
-    CYField *fields_;
-    CYMessage *messages_;
-
-    CYClass(CYIdentifier *name, CYExpression *super, CYField *fields, CYMessage *messages) :
-        name_(name),
-        super_(super),
-        fields_(fields),
-        messages_(messages)
-    {
-    }
-
-    virtual void Output(std::ostream &out) const;
-};
-
-struct CYFunctionParameter :
-    CYNext<CYFunctionParameter>,
-    CYThing
+struct CYLet :
+    CYStatement
 {
-    CYIdentifier *name_;
+    CYDeclarations *declarations_;
+    CYBlock code_;
 
-    CYFunctionParameter(CYIdentifier *name, CYFunctionParameter *next) :
-        CYNext<CYFunctionParameter>(next),
-        name_(name)
+    CYLet(CYDeclarations *declarations, CYStatement *statements) :
+        declarations_(declarations),
+        code_(statements)
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYFor :
@@ -713,7 +1216,8 @@ struct CYFor :
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYForIn :
@@ -730,119 +1234,160 @@ struct CYForIn :
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
-struct CYProperty :
-    CYNext<CYProperty>
+struct CYForEachIn :
+    CYStatement
 {
-    CYName *name_;
-    CYExpression *value_;
+    CYForInInitialiser *initialiser_;
+    CYExpression *set_;
+    CYStatement *code_;
 
-    CYProperty(CYName *name, CYExpression *value, CYProperty *next) :
-        CYNext<CYProperty>(next),
-        name_(name),
-        value_(value)
+    CYForEachIn(CYForInInitialiser *initialiser, CYExpression *set, CYStatement *code) :
+        initialiser_(initialiser),
+        set_(set),
+        code_(code)
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYObject :
     CYLiteral
 {
-    CYProperty *property_;
+    CYProperty *properties_;
 
-    CYObject(CYProperty *property) :
-        property_(property)
+    CYObject(CYProperty *properties = NULL) :
+        properties_(properties)
     {
     }
 
-    void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
+    void Output(CYOutput &out, CYFlags flags) const;
 };
 
-struct CYCatch :
-    CYThing
+struct CYMember :
+    CYExpression
 {
-    CYIdentifier *name_;
-    CYStatement *code_;
+    CYExpression *object_;
+    CYExpression *property_;
 
-    CYCatch(CYIdentifier *name, CYStatement *code) :
-        name_(name),
-        code_(code)
+    CYMember(CYExpression *object, CYExpression *property) :
+        object_(object),
+        property_(property)
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    void SetLeft(CYExpression *object) {
+        object_ = object;
+    }
+
+    void Replace_(CYContext &context);
 };
 
-struct CYSend :
-    CYExpression
+struct CYDirectMember :
+    CYMember
 {
-    CYExpression *self_;
-    CYArgument *arguments_;
-
-    CYSend(CYExpression *self, CYArgument *arguments) :
-        self_(self),
-        arguments_(arguments)
+    CYDirectMember(CYExpression *object, CYExpression *property) :
+        CYMember(object, property)
     {
     }
 
-    CYPrecedence(0)
+    CYPrecedence(1)
+    CYRightHand(false)
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
-struct CYMember :
-    CYExpression
+struct CYIndirectMember :
+    CYMember
 {
-    CYExpression *object_;
-    CYExpression *property_;
-
-    CYMember(CYExpression *object, CYExpression *property) :
-        object_(object),
-        property_(property)
+    CYIndirectMember(CYExpression *object, CYExpression *property) :
+        CYMember(object, property)
     {
     }
 
     CYPrecedence(1)
+    CYRightHand(false)
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
-struct CYNew :
+namespace cy {
+namespace Syntax {
+
+struct New :
     CYExpression
 {
     CYExpression *constructor_;
     CYArgument *arguments_;
 
-    CYNew(CYExpression *constructor, CYArgument *arguments) :
+    New(CYExpression *constructor, CYArgument *arguments) :
         constructor_(constructor),
         arguments_(arguments)
     {
     }
 
-    CYPrecedence(1)
+    virtual unsigned Precedence() const {
+        return arguments_ == NULL ? 2 : 1;
+    }
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    CYRightHand(false)
+
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
+
+    virtual CYExpression *AddArgument(CYContext &context, CYExpression *value);
 };
 
+} }
+
 struct CYCall :
     CYExpression
 {
     CYExpression *function_;
     CYArgument *arguments_;
 
-    CYCall(CYExpression *function, CYArgument *arguments) :
+    CYCall(CYExpression *function, CYArgument *arguments = NULL) :
         function_(function),
         arguments_(arguments)
     {
     }
 
-    CYPrecedence(2)
+    CYPrecedence(1)
+    CYRightHand(false)
+
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
+
+    virtual CYExpression *AddArgument(CYContext &context, CYExpression *value);
+};
+
+struct CYRubyProc;
+
+struct CYRubyBlock :
+    CYExpression
+{
+    CYExpression *call_;
+    CYRubyProc *proc_;
+
+    CYRubyBlock(CYExpression *call, CYRubyProc *proc) :
+        call_(call),
+        proc_(proc)
+    {
+    }
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    CYPrecedence(1)
+    CYRightHand(false)
+
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYIf :
@@ -852,14 +1397,15 @@ struct CYIf :
     CYStatement *true_;
     CYStatement *false_;
 
-    CYIf(CYExpression *test, CYStatement *_true, CYStatement *_false) :
+    CYIf(CYExpression *test, CYStatement *_true, CYStatement *_false = NULL) :
         test_(test),
         true_(_true),
         false_(_false)
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYDoWhile :
@@ -874,7 +1420,8 @@ struct CYDoWhile :
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYWhile :
@@ -889,38 +1436,75 @@ struct CYWhile :
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
-struct CYLambda :
-    CYExpression
-{
+// XXX: this should be split up into CYAnonymousFunction and CYNamedFunction (subclass)
+struct CYFunction {
     CYIdentifier *name_;
     CYFunctionParameter *parameters_;
-    CYSource *body_;
+    CYBlock code_;
+    CYNonLocal *nonlocal_;
 
-    CYLambda(CYIdentifier *name, CYFunctionParameter *parameters, CYSource *body) :
+    CYFunction(CYIdentifier *name, CYFunctionParameter *parameters, CYStatement *statements) :
         name_(name),
         parameters_(parameters),
-        body_(body)
+        code_(statements),
+        nonlocal_(NULL)
+    {
+    }
+
+    virtual ~CYFunction() {
+    }
+
+    void Inject(CYContext &context);
+    virtual void Replace_(CYContext &context, bool outer);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
+};
+
+// XXX: this should be split up into CYAnonymousFunctionExpression and CYNamedFunctionExpression
+struct CYFunctionExpression :
+    CYFunction,
+    CYExpression
+{
+    CYFunctionExpression(CYIdentifier *name, CYFunctionParameter *parameters, CYStatement *statements) :
+        CYFunction(name, parameters, statements)
     {
     }
 
     CYPrecedence(0)
+    CYRightHand(false)
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
-struct CYFunction :
-    CYLambda,
-    CYSource
+// XXX: this should derive from CYAnonymousFunctionExpression
+struct CYRubyProc :
+    CYFunctionExpression
 {
-    CYFunction(CYIdentifier *name, CYFunctionParameter *parameters, CYSource *body) :
-        CYLambda(name, parameters, body)
+    CYRubyProc(CYFunctionParameter *parameters, CYStatement *statements) :
+        CYFunctionExpression(NULL, parameters, statements)
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
+};
+
+// XXX: this should derive from CYNamedFunction
+struct CYFunctionStatement :
+    CYFunction,
+    CYStatement
+{
+    CYFunctionStatement(CYIdentifier *name, CYFunctionParameter *parameters, CYStatement *statements) :
+        CYFunction(name, parameters, statements)
+    {
+    }
+
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYExpress :
@@ -931,9 +1515,13 @@ struct CYExpress :
     CYExpress(CYExpression *expression) :
         expression_(expression)
     {
+        if (expression == NULL)
+            throw;
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Collapse(CYContext &context);
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYContinue :
@@ -946,7 +1534,8 @@ struct CYContinue :
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYBreak :
@@ -959,7 +1548,8 @@ struct CYBreak :
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYReturn :
@@ -972,46 +1562,85 @@ struct CYReturn :
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYEmpty :
     CYStatement
 {
-    virtual void Output(std::ostream &out) const;
-    virtual void Output(std::ostream &out, bool block) const;
+    virtual CYStatement *Collapse(CYContext &context);
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
+};
+
+struct CYFinally :
+    CYThing
+{
+    CYBlock code_;
+
+    CYFinally(CYStatement *statements) :
+        code_(statements)
+    {
+    }
+
+    void Replace(CYContext &context);
+    virtual void Output(CYOutput &out) const;
 };
 
-struct CYTry :
+namespace cy {
+namespace Syntax {
+
+struct Catch :
+    CYThing
+{
+    CYIdentifier *name_;
+    CYBlock code_;
+
+    Catch(CYIdentifier *name, CYStatement *statements) :
+        name_(name),
+        code_(statements)
+    {
+    }
+
+    void Replace(CYContext &context);
+    virtual void Output(CYOutput &out) const;
+};
+
+struct Try :
     CYStatement
 {
-    CYStatement *try_;
-    CYCatch *catch_;
-    CYStatement *finally_;
+    CYBlock code_;
+    Catch *catch_;
+    CYFinally *finally_;
 
-    CYTry(CYStatement *_try, CYCatch *_catch, CYStatement *finally) :
-        try_(_try),
+    Try(CYStatement *statements, Catch *_catch, CYFinally *finally) :
+        code_(statements),
         catch_(_catch),
         finally_(finally)
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
-struct CYThrow :
+struct Throw :
     CYStatement
 {
     CYExpression *value_;
 
-    CYThrow(CYExpression *value) :
+    Throw(CYExpression *value = NULL) :
         value_(value)
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
+} }
+
 struct CYWith :
     CYStatement
 {
@@ -1024,7 +1653,8 @@ struct CYWith :
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYSwitch :
@@ -1039,7 +1669,8 @@ struct CYSwitch :
     {
     }
 
-    virtual void Output(std::ostream &out) const;
+    virtual CYStatement *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYCondition :
@@ -1058,7 +1689,8 @@ struct CYCondition :
 
     CYPrecedence(15)
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
+    virtual void Output(CYOutput &out, CYFlags flags) const;
 };
 
 struct CYAddressOf :
@@ -1074,9 +1706,8 @@ struct CYAddressOf :
     }
 
     CYAlphabetic(false)
-    CYPrecedence(2)
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
 };
 
 struct CYIndirect :
@@ -1092,48 +1723,47 @@ struct CYIndirect :
     }
 
     CYAlphabetic(false)
-    CYPrecedence(1)
 
-    virtual void Output(std::ostream &out, CYFlags flags) const;
+    virtual CYExpression *Replace(CYContext &context);
 };
 
-#define CYPostfix_(op, name) \
+#define CYReplace \
+    virtual CYExpression *Replace(CYContext &context);
+
+#define CYPostfix_(op, name, args...) \
     struct CY ## name : \
         CYPostfix \
-    { \
+    { args \
         CY ## name(CYExpression *lhs) : \
             CYPostfix(lhs) \
         { \
         } \
-    \
-        CYPrecedence(3) \
     \
         virtual const char *Operator() const { \
             return op; \
         } \
     };
 
-#define CYPrefix_(alphabetic, op, name) \
+#define CYPrefix_(alphabetic, op, name, args...) \
     struct CY ## name : \
         CYPrefix \
-    { \
+    { args \
         CY ## name(CYExpression *rhs) : \
             CYPrefix(rhs) \
         { \
         } \
     \
         CYAlphabetic(alphabetic) \
-        CYPrecedence(4) \
     \
         virtual const char *Operator() const { \
             return op; \
         } \
     };
 
-#define CYInfix_(alphabetic, precedence, op, name) \
+#define CYInfix_(alphabetic, precedence, op, name, args...) \
     struct CY ## name : \
         CYInfix \
-    { \
+    { args \
         CY ## name(CYExpression *lhs, CYExpression *rhs) : \
             CYInfix(lhs, rhs) \
         { \
@@ -1147,16 +1777,14 @@ struct CYIndirect :
         } \
     };
 
-#define CYAssignment_(op, name) \
+#define CYAssignment_(op, name, args...) \
     struct CY ## name ## Assign : \
         CYAssignment \
-    { \
+    { args \
         CY ## name ## Assign(CYExpression *lhs, CYExpression *rhs) : \
             CYAssignment(lhs, rhs) \
         { \
         } \
-    \
-        CYPrecedence(16) \
     \
         virtual const char *Operator() const { \
             return op; \
@@ -1171,6 +1799,7 @@ CYPrefix_(true, "void", Void)
 CYPrefix_(true, "typeof", TypeOf)
 CYPrefix_(false, "++", PreIncrement)
 CYPrefix_(false, "--", PreDecrement)
+CYPrefix_(false, "+", Affirm)
 CYPrefix_(false, "-", Negate)
 CYPrefix_(false, "~", BitwiseNot)
 CYPrefix_(false, "!", LogicalNot)
@@ -1178,7 +1807,7 @@ CYPrefix_(false, "!", LogicalNot)
 CYInfix_(false, 5, "*", Multiply)
 CYInfix_(false, 5, "/", Divide)
 CYInfix_(false, 5, "%", Modulus)
-CYInfix_(false, 6, "+", Add)
+CYInfix_(false, 6, "+", Add, CYReplace)
 CYInfix_(false, 6, "-", Subtract)
 CYInfix_(false, 7, "<<", ShiftLeft)
 CYInfix_(false, 7, ">>", ShiftRightSigned)
@@ -1212,4 +1841,4 @@ CYAssignment_("&=", BitwiseAnd)
 CYAssignment_("^=", BitwiseXOr)
 CYAssignment_("|=", BitwiseOr)
 
-#endif/*CYPARSER_HPP*/
+#endif/*CYCRIPT_PARSER_HPP*/