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Re: empty arg in p:exec

From: Mike Sokolov <sokolov@ifactory.com>
Date: Fri, 19 Mar 2010 18:25:45 -0400
Message-ID: <4BA3F9E9.8030702@ifactory.com>
To: Romain Deltour <rdeltour@gmail.com>
CC: xproc-dev@w3.org
Wow - this is reminiscent of Make, which distinguishes between TAB and 
spaces - completely invisible to the programmer, but of critical 
importance for getting your Makefile to work properly.  It's not clear 
to me that there is any sort of valid use case for generating empty 
arguments by splitting up multiple spaces, is there?  Maybe it was 
spec'd that way to make it easier for implementers?

On 03/19/2010 04:59 AM, Romain Deltour wrote:
> Hi,
>
> I recently came up against a quite puzzling issue... What would you 
> expect the following step to do in Calabash ?
>
> <p:exec command="tidy" source-is-xml="false" result-is-xml="true" 
> wrap-result-lines="false">
> <p:with-option name="args" select="'-asxml --quiet yes  
> --show-warnings no'"/>
> </p:exec>
>
> It actually fails with: Error: Can't open ""
>
> The issue is caused by the double space between "-quiet yes" and 
> "-show-warnings no". The default args separator is a space, which 
> means that the arg list computed by Calabash is 
> [-asxml,--quiet,yes,,--show-warnings,no]. It took me a while to get 
> over this one!
>
> It might be better to ignore empty parameters, or do you think it's a 
> worthy feature rather than a bug ?
>
> BR,
> Romain.
>
Received on Friday, 19 March 2010 22:26:18 GMT

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