From: Jake McArthur <jake.mcarthur@...>
Date: 2006-07-27T17:16:57+09:00
Subject: Re: ||= in an expression

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On Jul 27, 2006, at 3:10 AM, rejoc wrote:

> Hello,
>
> I new to Ruby and curious about this language I do use (yeet).
>
> I was browsing through some libraries/modules and I found a line  
> looking like
>
> a[:i] ||= "a string"
>
> I could not find this syntax in any manual online (and googling "|| 
> =" is not of much help :-( )
>
> Can anyone tell me what it means
>
> TiA
>

Consider:

"some string" || "a string"

versus:

nil || "a string"

The former returns "some string", but the latter returns "a string".  
Apply that to the form you described and it basically means that if a 
[:i] is nil then it assigns "a string", otherwise it leaves it alone.

- Jake McArthur
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