---

skInterpreter Class Reference

This class parses and executes Simkin script, and holds a list of global variables. More...

#include <skInterpreter.h>

Inheritance diagram for skInterpreter:

List of all members.

Public Member Functions
skMethodDefNode *	parseString (const skString &location, const skString &code, skExecutableContext &ctxt)
	this function parses the script in the code variable and returns a parse tree if there are no syntax errors.
skMethodDefNode *	parseExternalParams (const skString &location, skStringList &paramNames, const skString &code, skExecutableContext &ctxt)
	this function parses the script in the code variable and returns a parse tree if there are no syntax errors.
void	executeString (const skString &location, skiExecutable *obj, const skString &code, skRValueArray &args, skRValue &return_value, skMethodDefNode **parseTree, skExecutableContext &ctxt)
	this function parses and executes script which is assumed to belong to the object passed in.
void	executeStringExternalParams (const skString &location, skiExecutable *obj, skStringList &paramNames, const skString &code, skRValueArray &args, skRValue &r, skMethodDefNode **keepParseTree, skExecutableContext &ctxt)
	this function parses and executes script with externally declared parameters which is assumed to belong to the object passed in.
void	executeParseTree (const skString &location, skiExecutable *obj, skMethodDefNode *parseTree, skRValueArray &args, skRValue &return_value, skExecutableContext &ctxt)
	this function executes some script that has already been parsed into a parse tree.
void	evaluateExpression (const skString &location, skiExecutable *obj, const skString &expression, skRValueTable &vars, skRValue &return_value, skExecutableContext &ctxt)
	this function parses and evaluates an expression within the given context
void	evaluateExpression (const skString &location, skiExecutable *obj, skExprNode *expression, skRValueTable &vars, skRValue &return_value, skExecutableContext &ctxt)
	this function parses and evaluates an expression within the given context
void	addGlobalVariable (const skString &name, const skRValue &value)
	this method adds a global variable to the list held by this interpreter.
void	removeGlobalVariable (const skString &name)
	this method removes a global variable from the list held by this interpreter
bool	findGlobalVariable (const skString &name, skRValue &return_value)
	this method finds the value of a global variable by name
const skRValueTable &	getGlobalVariables () const
	this method returns the table of global variables
virtual bool	setValue (const skString &s, const skString &attribute, const skRValue &v)
	this method is used to set the Tracing variable in the interpreter.
virtual bool	getValue (const skString &s, const skString &attribute, skRValue &v)
	this method is used to retrieve the Tracing variable in the interpreter.
virtual bool	method (const skString &method_name, skRValueArray &arguments, skRValue &return_value, skExecutableContext &ctxt)
	Requests that the object execute the given method.
virtual void	getInstanceVariables (skRValueTable &table)
	This method returns the instance variables for this object.
void	trace (const skString &msg)
	output a message to the current trace output
void	trace (const Char *msg)
	output a message to the current trace output
void	setTraceCallback (skTraceCallback *callback)
	this method sets an object to receive trace messages.
void	setStatementStepper (skStatementStepper *stepper)
	this method sets an object to be called each time a statement is executed.
void	runtimeError (skStackFrame &ctxt, const skString &msg)
	This method reports a runtime error by throwing a skRuntimeException.
void	runtimeError (skStackFrame &ctxt, const Char *msg)
	This method reports a runtime error by throwing a skRuntimeException.
	skInterpreter ()
	Constructor - adds the interpreter as a global variable with the name "Interpreter".
virtual	~skInterpreter ()
	Destructor - deletes the global variable list.
void	init ()
	init function

---

Detailed Description

This class parses and executes Simkin script, and holds a list of global variables.

There is one global Interpreter object which you should set up at the start, although others can also be created.

---

Constructor & Destructor Documentation

skInterpreter::skInterpreter (   )

Constructor - adds the interpreter as a global variable with the name "Interpreter". Remarks: in Symbian version - you should call init() separately to add the interpreter global variable, as this may leave

---

Member Function Documentation

void skInterpreter::addGlobalVariable (  const skString &  name, const skRValue &  value )

this method adds a global variable to the list held by this interpreter. If the variable already has a value, it is replaced with the new one Parameters: name  - the name of the global variable value  - the value of the global variable, which can be any RValue Exceptions: Symbian  - a leaving function

void skInterpreter::evaluateExpression (  const skString &  location, skiExecutable *  obj, skExprNode *  expression, skRValueTable &  vars, skRValue &  return_value, skExecutableContext &  ctxt )

this function parses and evaluates an expression within the given context Parameters: location  - a textual description of the location of the expression (this appears in error messages) obj  - the executable object which "owns" the expression vars  - a table of local variables defined for the expression expression  - a single Simkin expression in a parse tree created by parseExpression return_value  - an RValue which receives the result of the expression ctxt  context object to receive errors Exceptions: skParseException  - if a syntax error is encountered skRuntimeException  - if an error occurs while the expression is evaluated Symbian  - a leaving function

void skInterpreter::evaluateExpression (  const skString &  location, skiExecutable *  obj, const skString &  expression, skRValueTable &  vars, skRValue &  return_value, skExecutableContext &  ctxt )

this function parses and evaluates an expression within the given context Parameters: location  - a textual description of the location of the expression (this appears in error messages) obj  - the executable object which "owns" the expression vars  - a table of local variables defined for the expression expression  - a single Simkin expression which must begin with "=", for example "=a+b" return_value  - an RValue which receives the result of the expression ctxt  context object to receive errors Exceptions: skParseException  - if a syntax error is encountered skRuntimeException  - if an error occurs while the expression is evaluated Symbian  - a leaving function

void skInterpreter::executeParseTree (  const skString &  location, skiExecutable *  obj, skMethodDefNode *  parseTree, skRValueArray &  args, skRValue &  return_value, skExecutableContext &  ctxt )

this function executes some script that has already been parsed into a parse tree. Parameters: location  - a textual description of the location of the script (this appears in error messages) obj  - the executable object which "owns" the script parseTree  - a parse tree that has been generated by one of the parse or execute functions of the Interpreter args  - an array of arguments to the function, which are passed as parameters to the script ctxt  context object to receive errors return_value  - an RValue which receives the result of the script Exceptions: skRuntimeException  - if an error occurs while the script is running Symbian  - a leaving function

void skInterpreter::executeString (  const skString &  location, skiExecutable *  obj, const skString &  code, skRValueArray &  args, skRValue &  return_value, skMethodDefNode **  parseTree, skExecutableContext &  ctxt )

this function parses and executes script which is assumed to belong to the object passed in. Parameters: location  - a textual description of the location of the script (this appears in error messages) obj  - the executable object which "owns" the script args  - an array of arguments to the function, which are passed as parameters to the script code  - a string of Simkin script, including parameter declarations return_value  - an RValue which receives the result of the script parseTree  - if you supply this pointer, the parse tree is assigned to it, and you must delete it yourself. Without the parameter the parse tree will be deleted by the interpreter. The parse tree can be used in a cache and passed to executeParseTree later. ctxt  context object to receive errors Exceptions: skParseException  - if a syntax error is encountered skRuntimeException  - if an error occurs while the script is running Symbian  - a leaving function

void skInterpreter::executeStringExternalParams (  const skString &  location, skiExecutable *  obj, skStringList &  paramNames, const skString &  code, skRValueArray &  args, skRValue &  r, skMethodDefNode **  keepParseTree, skExecutableContext &  ctxt )

this function parses and executes script with externally declared parameters which is assumed to belong to the object passed in. Parameters: location  - a textual description of the location of the script (this appears in error messages) obj  - the executable object which "owns" the script paramNames  - a list of parameter names (hence the name "ExternalParams" args  - an array of arguments to the function, which are passed as parameters to the script code  - a string of Simkin script, which does *not* include parameter declarations r  - an RValue which receives the result of the script keepParseTree  - if you supply this pointer, the parse tree is assigned to it, and you must delete it yourself. Without the parameter the parse tree will be deleted by the interpreter. The parse tree can be used in a cache and passed to executeParseTree later. ctxt  context object to receive errors Exceptions: skParseException  - if a syntax error is encountered skRuntimeException  - if an error occurs while the script is running Symbian  - a leaving function

bool skInterpreter::findGlobalVariable (  const skString &  name, skRValue &  return_value )

this method finds the value of a global variable by name Parameters: name  - the name of the global variable return_value  - an RValue which receives the value of the variable Returns: true if the variable was found, otherwise false

const skRValueTable & skInterpreter::getGlobalVariables (   )  const

this method returns the table of global variables Returns: a hashtable of global variables mapping name to object

void skInterpreter::getInstanceVariables (  skRValueTable &  table  )  [virtual]

This method returns the instance variables for this object. Parameters: table  a table to filled with references to the instance variables Exceptions: Symbian  - a leaving function Reimplemented from skExecutable.

bool skInterpreter::getValue (  const skString &  s, const skString &  attribute, skRValue &  v )  [virtual]

this method is used to retrieve the Tracing variable in the interpreter. If true, method calls will show in the trace as the script is executed In Simkin call tracing=Interpreter.Tracing Reimplemented from skExecutable.

void skInterpreter::init (   )

init function Remarks: needs to be called explicitly in Symbian version Exceptions: Symbian  - a leaving function

bool skInterpreter::method (  const skString &  method_name, skRValueArray &  arguments, skRValue &  return_value, skExecutableContext &  ctxt )  [virtual]

Requests that the object execute the given method. Methods supported: breakpoint - breaks to the debugger (if present) Parameters: method_name  - the name of the method to execute arguments  - an array of RValue objects, which are the arguments to the method return_value  - an object to receive the return value of the method ctxt  context object to receive errors Returns: true if the method could be executed, or false if the method is not supported Exceptions: skParseException  - if a syntax error is encountered while the script is running skRuntimeException  - if an error occurs while the script is running Reimplemented from skExecutable.

skMethodDefNode * skInterpreter::parseExternalParams (  const skString &  location, skStringList &  paramNames, const skString &  code, skExecutableContext &  ctxt )

this function parses the script in the code variable and returns a parse tree if there are no syntax errors. It assumes that the script does *not* contain parameters and enclosing braces. If there are syntax errors the function throws an skParseException object Parameters: location  - a string describing where this code is located, this will appear in any error messages paramNames  - a list of parameter names (hence the name "ExternalParams" code  - a string of Simkin code, which does *not* include the parameter declarations ctxt  context object to receive errors Returns: returns a parse tree, if the syntax was valid. The caller must free this tree. Exceptions: skParseException  - if a syntax error is encountered Symbian  - a leaving function

skMethodDefNode * skInterpreter::parseString (  const skString &  location, const skString &  code, skExecutableContext &  ctxt )

this function parses the script in the code variable and returns a parse tree if there are no syntax errors. If there are syntax errors the function throws an skParseException object Parameters: location  - a string describing where this code is located, this will appear in any error messages code  - a string of Simkin code, which includes the parameter declarations ctxt  context object to receive errors Returns: returns a parse tree, if the syntax was valid. The caller must free this tree. Exceptions: skParseException  - if a syntax error is encountered Symbian  - a leaving function

void skInterpreter::removeGlobalVariable (  const skString &  name  )

this method removes a global variable from the list held by this interpreter Parameters: name  - the name of the global variable

void skInterpreter::runtimeError (  skStackFrame &  ctxt, const Char *  msg )

This method reports a runtime error by throwing a skRuntimeException. Parameters: ctxt  - the current source code context msg  - a message describing the error Exceptions: Symbian  - a leaving function

void skInterpreter::runtimeError (  skStackFrame &  ctxt, const skString &  msg )

This method reports a runtime error by throwing a skRuntimeException. Parameters: ctxt  - the current source code context msg  - a message describing the error Exceptions: Symbian  - a leaving function

void skInterpreter::setStatementStepper (  skStatementStepper *  stepper  )

this method sets an object to be called each time a statement is executed. Parameters: stepper  the stepper object, or 0 to clear

void skInterpreter::setTraceCallback (  skTraceCallback *  callback  )

this method sets an object to receive trace messages. Pass 0 to fall back to standard mechanism (using skTracer) Parameters: callback  the callback object, or 0 to fall back to using skTracer

bool skInterpreter::setValue (  const skString &  s, const skString &  attribute, const skRValue &  v )  [virtual]

this method is used to set the Tracing variable in the interpreter. This will show method calls as the script is executed In Simkin call Interpreter.Tracing=true Reimplemented from skExecutable.

void skInterpreter::trace (  const Char *  msg  )

output a message to the current trace output Parameters: msg  the message to show

void skInterpreter::trace (  const skString &  msg  )

output a message to the current trace output Parameters: msg  the message to show

---

The documentation for this class was generated from the following files:

• skInterpreter.h
• skInterpreter.cpp
• skInterpreterNode.cpp

---