From: Eric Hodel <drbrain@...7.net>
Date: 2005-03-17T06:03:22+09:00
Subject: Re: Symbol vs String

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On 16 Mar 2005, at 12:37, Sebesty=E9n G=E1bor wrote:

> Hi,
>
> Just a dumb question: what is the real difference between { :aKey =3D>=20=

> "aValue" } and { "aKey" =3D> "aValue" } ? I know the first key is a=20
> symbol the latter is a string. I like string keys why should I use=20
> symbols? Why symbols worth to use as keys?

Symbols take up less memory space (only allocated once for the same=20
Symbol) and have a faster #hash function (#object_id, not computed).

'x' =3D=3D 'x' # =3D> true
'x'.object_id =3D=3D 'x'.object_id # =3D> false

:x =3D=3D :x # =3D> true
:x.object_id =3D=3D :x.object_id # =3D> true

--=20
Eric Hodel - drbrain@segment7.net - http://segment7.net
FEC2 57F1 D465 EB15 5D6E  7C11 332A 551C 796C 9F04

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