slogo.instruction

Class NotEqual

java.lang.Object

slogo.GrammarElement

slogo.instruction.Instruction

slogo.instruction.NotEqual

public class NotEqual
extends Instruction

A NOTEQUAL instruction has two components: a GrammarElement that represents the first double and a GrammarElement that represents the second double To evaluate a NOTEQUAL instruction the expressions are evaluated first, this determines then double version of the numbers. If the numbers are equal, return 0; else, return 1.

The value returned by evaluating a NOTEQUAL instruction is the instruction itself, representing the first and second GrammarElements.

Field Summary

Fields

Modifier and Type	Field and Description
private GrammarElement	expressionOne
private GrammarElement	expressionTwo

Fields inherited from class slogo.GrammarElement

gelementsToValue

Constructor Summary

Constructors

Constructor and Description
NotEqual(GrammarElement e, GrammarElement f) Constructs a NOTEQUAL instruction that can be executed.

Method Summary

Modifier and Type	Method and Description
java.lang.Object	evaluate(Context c) Evaluate this instruction in a Context.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

expressionOne

private GrammarElement expressionOne

expressionTwo

private GrammarElement expressionTwo

Constructor Detail

NotEqual

public NotEqual(GrammarElement e,
                GrammarElement f)

Constructs a NOTEQUAL instruction that can be executed.

Parameters:

e - the first number to compare

f - the second number to compare

Method Detail

evaluate

public java.lang.Object evaluate(Context c)

Evaluate this instruction in a Context.

Specified by:

evaluate in class Instruction

Parameters:

c - the Context for the evaluation

Returns:

0 or 1, depending on the values of the the expressions

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

Returns:

a String representing this instruction as NOTEQUAL, followed by the two expressions