slogo.expression

Class Expression

java.lang.Object

slogo.GrammarElement

slogo.expression.Expression

Direct Known Subclasses:

BinaryExpression, Number, UnaryExpression, Variable

public abstract class Expression
extends GrammarElement

The base class of all arithmetic expressions, the evaluate method uses the hook/template method value to return a Double value, the template method returns a double.

Field Summary

Fields inherited from class slogo.GrammarElement

gelementsToValue

Constructor Summary

Constructors

Constructor and Description
Expression()

Method Summary

Methods

Modifier and Type	Method and Description
java.lang.Double	evaluate(Context c) uses the hook/template method value to return a Double
abstract double	value(Context c)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Expression

public Expression()

Method Detail

evaluate

public java.lang.Double evaluate(Context c)

uses the hook/template method value to return a Double

Specified by:

evaluate in class GrammarElement

Parameters:

c - the context of the expression--may affect the value

Returns:

the result of evaluating the construct

value

public abstract double value(Context c)