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Date: Sat, 17 Nov 2012 14:56:29 -0800
From: Ray Andrews <rayandrews@eastlink.ca>
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Subject: Re: ${var: -1:1} vs. ${var:-1:1}
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On 17/11/12 01:48 PM, Moritz Bunkus wrote:
> Hey,
>
> if you don't put a space there then the parser thinks that this the
> "${variable:-default} syntax which means "expands to the variable's
> content if the variable is set and to 'default' if it is unset". Can
> be seen easily with:
>
> [0 mosu@sweet-chili ~] echo ${thisvarisnotset:-1:1}
> 1:1
>
> So the '1:1' is interpreted as the 'default'. You probably never saw
> that result because you were trying to extract the last character from
> a string, meaning you always used a variable that was set.
>
> Kind regards,
> mosu
>
I see.  But it's still lousy syntax IMHO.