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/*
* This file is part of the KDE libraries
* Copyright (C) 1999-2001 Harri Porten ([email protected])
* Copyright (C) 2001 Peter Kelly ([email protected])
* Copyright (C) 2003 Apple Computer, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#ifndef _KJS_INTERPRETER_H_
#define _KJS_INTERPRETER_H_
#include "value.h"
#include "object.h"
#include "types.h"
namespace KJS {
class ContextImp;
class InterpreterImp;
/**
* The three different types of code that can be executed in a Context.
* These are:
* <ul>
* <li>GlobalCode - code executed as a result of a call to
* Interpreter::evaluate().</li>
* <li>EvalCode - executed by a call to the builtin eval() function</li>
* <li>FunctionCode - inside a function call (ECMAScript functions only;
* does not include builtin native functions or funcitons supplied by the
* host environment</li>
* </ul>
*/
enum CodeType {
GlobalCode = 0,
EvalCode = 1,
FunctionCode = 2
};
/**
* Represents an execution context, as specified by section 10 of the ECMA
* spec.
*
* An execution context contains information about the current state of the
* script - the scope for variable lookup, the value of "this", etc. A new
* execution context is entered whenever global code is executed (e.g. with
* Interpreter::evaluate()), a function is called (see
* Object::call()), or the builtin "eval" function is executed.
*
* Most inheritable functions in the KJS api take a ExecState pointer as
* their first parameter. This can be used to obtain a handle to the current
* execution context.
*
* Note: Context objects are wrapper classes/smart pointers for the internal
* KJS ContextImp type. When one context variable is assigned to another, it
* is still referencing the same internal object.
*/
class KJS_EXPORT Context {
public:
Context(ContextImp *i) : rep(i) { }
ContextImp *imp() const { return rep; }
/**
* Returns the scope chain for this execution context. This is used for
* variable lookup, with the list being searched from start to end until a
* variable is found.
*
* @return The execution context's scope chain
*/
const ScopeChain &scopeChain() const;
/**
* Returns the variable object for the execution context. This contains a
* property for each variable declared in the execution context.
*
* @return The execution context's variable object
*/
Object variableObject() const;
/**
* Returns the "this" value for the execution context. This is the value
* returned when a script references the special variable "this". It should
* always be an Object, unless application-specific code has passed in a
* different type.
*
* The object that is used as the "this" value depends on the type of
* execution context - for global contexts, the global object is used. For
* function objewcts, the value is given by the caller (e.g. in the case of
* obj.func(), obj would be the "this" value). For code executed by the
* built-in "eval" function, the this value is the same as the calling
* context.
*
* @return The execution context's "this" value
*/
Object thisValue() const;
/**
* Returns the context from which the current context was invoked. For
* global code this will be a null context (i.e. one for which
* isNull() returns true). You should check isNull() on the returned
* value before calling any of it's methods.
*
* @return The calling execution context
*/
const Context callingContext() const;
/**
* The type of code being executed in this context. One of GlobalCode,
* EvalCode or FunctionCode
*/
CodeType codeType() const;
/**
* The identifier of the source code fragment containing the code being
* executed
*/
int sourceId() const;
/**
* The line number on which the current statement begins
*/
int curStmtFirstLine() const;
/**
* The line number on which the current statement ends
*/
int curStmtLastLine() const;
/**
* In the case of FunctionCode, the function objects being called
*/
Object function() const;
/**
* In the case of FunctionCode, the name of the function being called
*/
Identifier functionName() const;
/**
* In the case of FunctionCode, the arguments passed to the function
*/
List args() const;
private:
ContextImp *rep;
};
bool operator==(const Context &c1, const Context &c2);
bool operator!=(const Context &c1, const Context &c2);
/**
* Interpreter objects can be used to evaluate ECMAScript code. Each
* interpreter has a global object which is used for the purposes of code
* evaluation, and also provides access to built-in properties such as
* " Object" and "Number".
*/
class KJS_EXPORT Interpreter {
public:
/**
* Creates a new interpreter. The supplied object will be used as the global
* object for all scripts executed with this interpreter. During
* constuction, all the standard properties such as "Object" and "Number"
* will be added to the global object.
*
* Note: You should not use the same global object for multiple
* interpreters.
*
* This is due do the fact that the built-in properties are set in the
* constructor, and if these objects have been modified from another
* interpreter (e.g. a script modifying String.prototype), the changes will
* be overridden.
*
* @param global The object to use as the global object for this interpreter
*/
Interpreter(const Object &global);
/**
* Creates a new interpreter. A global object will be created and
* initialized with the standard global properties.
*/
Interpreter();
virtual ~Interpreter();
/**
* Returns the object that is used as the global object during all script
* execution performed by this interpreter
*/
Object &globalObject() const;
void initGlobalObject();
static void lock();
static void unlock();
/**
* Returns the execution state object which can be used to execute
* scripts using this interpreter at a the "global" level, i.e. one
* with a execution context that has the global object as the "this"
* value, and who's scope chain contains only the global object.
*
* Note: this pointer remains constant for the life of the interpreter
* and should not be manually deleted.
*
* @return The interpreter global execution state object
*/
ExecState *globalExec();
/**
* Parses the supplied ECMAScript code and checks for syntax errors.
*
* @param code The code to check
* @param errLine Returns the line the error was on (if there was one).
* @param errMsg Returns the error message (if there was one).
* @return true if there were no syntax errors in the code, otherwise false
*/
bool checkSyntax(const UString &code, int *errLine, UString *errMsg);
/**
* Parses the supplied ECMAScript code and checks for syntax errors.
*
* @param code The code to check
* @return true if there were no syntax errors in the code, otherwise false
*/
bool checkSyntax(const UString &code);
/**
* Evaluates the supplied ECMAScript code.
*
* Since this method returns a Completion, you should check the type of
* completion to detect an error or before attempting to access the returned
* value. For example, if an error occurs during script execution and is not
* caught by the script, the completion type will be Throw.
*
* If the supplied code is invalid, a SyntaxError will be thrown.
*
* @param code The code to evaluate
* @param thisV The value to pass in as the "this" value for the script
* execution. This should either be Null() or an Object.
* @return A completion object representing the result of the execution.
*/
Completion evaluate(const UString &code, const Value &thisV = Value());
/**
* @internal
*
* Returns the implementation object associated with this interpreter.
* Only useful for internal KJS operations.
*/
InterpreterImp *imp();
/**
* Returns the builtin "Object" object. This is the object that was set
* as a property of the global object during construction; if the property
* is replaced by script code, this method will still return the original
* object.
*
* @return The builtin "Object" object
*/
Object builtinObject() const;
/**
* Returns the builtin "Function" object.
*/
Object builtinFunction() const;
/**
* Returns the builtin "Array" object.
*/
Object builtinArray() const;
/**
* Returns the builtin "Boolean" object.
*/
Object builtinBoolean() const;
/**
* Returns the builtin "String" object.
*/
Object builtinString() const;
/**
* Returns the builtin "Number" object.
*/
Object builtinNumber() const;
/**
* Returns the builtin "Date" object.
*/
Object builtinDate() const;
/**
* Returns the builtin "RegExp" object.
*/
Object builtinRegExp() const;
/**
* Returns the builtin "Error" object.
*/
Object builtinError() const;
/**
* Returns the builtin "Object.prototype" object.
*/
Object builtinObjectPrototype() const;
/**
* Returns the builtin "Function.prototype" object.
*/
Object builtinFunctionPrototype() const;
/**
* Returns the builtin "Array.prototype" object.
*/
Object builtinArrayPrototype() const;
/**
* Returns the builtin "Boolean.prototype" object.
*/
Object builtinBooleanPrototype() const;
/**
* Returns the builtin "String.prototype" object.
*/
Object builtinStringPrototype() const;
/**
* Returns the builtin "Number.prototype" object.
*/
Object builtinNumberPrototype() const;
/**
* Returns the builtin "Date.prototype" object.
*/
Object builtinDatePrototype() const;
/**
* Returns the builtin "RegExp.prototype" object.
*/
Object builtinRegExpPrototype() const;
/**
* Returns the builtin "Error.prototype" object.
*/
Object builtinErrorPrototype() const;
/**
* The initial value of "Error" global property
*/
Object builtinEvalError() const;
Object builtinRangeError() const;
Object builtinReferenceError() const;
Object builtinSyntaxError() const;
Object builtinTypeError() const;
Object builtinURIError() const;
Object builtinEvalErrorPrototype() const;
Object builtinRangeErrorPrototype() const;
Object builtinReferenceErrorPrototype() const;
Object builtinSyntaxErrorPrototype() const;
Object builtinTypeErrorPrototype() const;
Object builtinURIErrorPrototype() const;
enum CompatMode { NativeMode, IECompat, NetscapeCompat };
/**
* Call this to enable a compatibility mode with another browser.
* (by default konqueror is in "native mode").
* Currently, in KJS, this only changes the behavior of Date::getYear()
* which returns the full year under IE.
*/
void setCompatMode(CompatMode mode);
CompatMode compatMode() const;
/**
* Run the garbage collection. Returns true when at least one object
* was collected; false otherwise.
*/
static bool collect();
/**
* Called by InterpreterImp during the mark phase of the garbage collector
* Default implementation does nothing, this exist for classes that reimplement Interpreter.
*/
virtual void mark() {}
/**
* Provides a way to distinguish derived classes.
* Only useful if you reimplement Interpreter and if different kind of
* interpreters are created in the same process.
* The base class returns 0, the ECMA-bindings interpreter returns 1.
*/
virtual int rtti() { return 0; }
#ifdef KJS_DEBUG_MEM
/**
* @internal
*/
static void finalCheck();
#endif
private:
InterpreterImp *rep;
/**
* This constructor is not implemented, in order to prevent
* copy-construction of Interpreter objects. You should always pass around
* pointers to an interpreter instance instead.
*/
Interpreter(const Interpreter&);
/**
* This constructor is not implemented, in order to prevent assignment of
* Interpreter objects. You should always pass around pointers to an
* interpreter instance instead.
*/
Interpreter operator=(const Interpreter&);
protected:
virtual void virtual_hook( int id, void* data );
};
/**
* Represents the current state of script execution. This object allows you
* obtain a handle the interpreter that is currently executing the script,
* and also the current execution state context.
*/
class KJS_EXPORT ExecState {
friend class InterpreterImp;
friend class FunctionImp;
friend class GlobalFuncImp;
friend class TryNode;
friend class VarDeclNode;
friend class FuncDeclNode;
public:
/**
* Returns the interpreter associated with this execution state
*
* @return The interpreter executing the script
*/
// ### make non-const or provide an overload pair
Interpreter *dynamicInterpreter() const { return _interpreter; }
// for compatibility
Interpreter *interpreter() const { return dynamicInterpreter(); }
/**
* Returns the interpreter associated with the current scope's
* global object
*
* @return The interpreter currently in scope
*/
Interpreter *lexicalInterpreter() const;
/**
* Returns the execution context associated with this execution state
*
* @return The current execution state context
*/
Context context() const { return _context; }
void setException(const Value &e);
void clearException();
Value exception() const { return _exception; }
// ### make const
bool hadException();
/*
* request for ending execution with an exception
*/
static void requestTerminate() { terminate_request = true; }
/*
* optional confirmation for ending execution after requestTerminate()
*/
static bool (*confirmTerminate)();
private:
ExecState(Interpreter *interp, ContextImp *con)
: _interpreter(interp), _context(con) { }
Interpreter *_interpreter;
ContextImp *_context;
Value _exception;
static bool terminate_request;
};
} // namespace
#endif // _KJS_INTERPRETER_H_
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