Ruby v1.6 Class and Library Reference: NilClass

class NilClass |
Parent: | Object
Version: | 1.6

### Index:

& ^ | nil? to_a to_i to_s

The class of the singleton object `nil`.

instance methods
& | `nil` & anObject -> `false`
|  | And-Returns `false`. As anObject is an argument to a method call, it is always evaluated; there is no short-circuit evaluation in this case.
    nil && puts("logical and")
    nil &  puts("and")
produces:
    and
^ | `nil` ^ anObject -> `true` or `false`
|  | Exclusive Or-Returns `false` if anObject is `nil` or `false`, `true` otherwise.
| | `nil` | anObject -> `true` or `false`
|  | Or-Returns `false` if anObject is `nil` or `false`, `true` otherwise.
nil? | `nil`.nil? -> `true`
|  | Always returns `true`.
to_a | `nil`.to_a -> []
|  | Always returns an empty array.
to_i | `nil`.to_i -> 0
|  | Always returns zero.
to_s | `nil`.to_s -> ""
|  | Always returns the empty string.

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.