Re: [[ and [

[Peter Stephenson <Peter.Stephenson@xxxxxxx>]

On Tue, 6 Mar 2012 11:35:32 +0000
Peter Stephenson <Peter.Stephenson@xxxxxxx> wrote:
> However,
> 
>   [[ $foo -eq "" ]]
> 
> does exactly what it looks like it does

Sigh.  Sort of.  [ ... -eq ...] and [[ ... -eq ... ]] are numeric tests,
so if foo is a string of zeros it's not doing what it looks like.  I
should have said

  [ $foo = "" ]]

and

  [[ $foo = "" ]]

or

  [[ $foo == "" ]]

I don't know why it's that way round, it seems a bit illogical (which is
why Perl is the other way), but it always has been that way.

-- 
Peter Stephenson <pws@xxxxxxx>            Software Engineer
Tel: +44 (0)1223 692070                   Cambridge Silicon Radio Limited
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