Programming Ruby

The Pragmatic Programmer's Guide

Previous < Contents ^
Next >
class TrueClass
Parent: Object
Version: 1.6

Index:

& ^ |


The global value true is the only instance of class TrueClass and represents a logically true value in boolean expressions. The class provides operators allowing true to be used in logical expressions.

instance methods
& true & anObject -> anObject

And---Returns false if anObject is nil or false, true otherwise.

^ true ^ anObject -> !anObject

Exclusive Or---Returns true if anObject is nil or false, false otherwise.

| true | anObject -> true

Or---Returns true. As anObject is an argument to a method call, it is always evaluated; there is no short-circuit evaluation in this case.

true |  puts("or")
true || puts("logical or")
produces:
or


Previous < Contents ^
Next >

Extracted from the book "Programming Ruby - The Pragmatic Programmer's Guide"
Copyright © 2000 Addison Wesley Longman, Inc. Released under the terms of the Open Publication License V1.0.
This reference is available for download.