From: Tony Arcieri <tony.arcieri@...>
Date: 2010-06-02T23:24:55+09:00
Subject: Re: having a class method called only one time ?

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You can "memoize" the result of such an operation in an instance variable b=
y
doing

@cached_result ||=3D big_expensive_operation

This will use the value of @cached_result unless it's unset/nil, otherwise
it will invoke the expensive operation and store the result in an ivar

2010/6/2 Une B=E9vue <unbewusst.sein@google.com.invalid>

> I'd like having a class method called only one time ?
> Is it possible ?
>
> suppose i do have a class "HFSFile" and i need to know the host ip.
>
> i don't want to call the method giving host ip each time i need it but
> only the first time even i do instantiate several HFSFile, mostly
> because it's time consuming :
>
> @h[:host_ip] =3D `curl -s http://whatismyip.org`.chomp
>
> it is even in a while loop because sometimes curl returns ''.
>
>
> --
>  =AB Les faiblesses des hommes font la force des femmes. =BB
>   (Voltaire)
>
>


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Tony Arcieri
Medioh! A Kudelski Brand

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