# Programming Ruby ### The Pragmatic Programmer's Guide
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class Symbol |
Parent: | Object
Version: | 1.6

### Index:

id2name inspect to_i to_s

A `Symbol` object represents a Ruby name and is generated automatically using the `:name` literal syntax. The same `Symbol` object will be created for a given name string for the duration of a program's execution, regardless of the context or meaning of that name. Thus if `Fred` is a constant in one context, a method in another, and a class in a third, the `Symbol` `:Fred` will be the same object in all three contexts.

`module One`
`class Fred`
`end`
`$f1 = :Fred`
`end`
`module Two`
`Fred = 1`
`$f2 = :Fred`
`end`
`def Fred()`
`end`
`$f3 = :Fred`
`$f1.id` | » | `2305294`
`$f2.id` | » | `2305294`
`$f3.id` | » | `2305294`

instance methods
id2name | sym.id2name -> aString
|  | Returns the name corresponding to sym.
`:fred.id2name` | » | `"fred"`
inspect | sym.inspect -> aString
|  | Returns the representation of sym as a symbol literal.
`:fred.inspect` | » | `":fred"`
to_i | sym.to_i -> aFixnum
|  | Returns an integer that is unique for each symbol within a particular execution of a program.
to_s | sym.to_s -> aString
|  | Synonym for `Symbol#id2name` .

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Extracted from the book "Programming Ruby - The Pragmatic Programmer's Guide"
Copyright © 2001 by Addison Wesley Longman, Inc. This material may be distributed only subject to the terms and conditions set forth in the Open Publication License, v1.0 or later (the latest version is presently available at http://www.opencontent.org/openpub/)).

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