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Re: Substring expansion error when offset contains a colon

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On 10/19/15 3:45 AM, grishalevit@gmail.com wrote:
> When using ${parameter:offset:length} expansion, the parser doesn't account for all the ways that a colon can appear in "offset".
> 
> For example:
> 
> $ echo ${PARAM:${OFFSET:-0}}
> -bash: ${OFFSET: bad substitution
> 
> or:
> 
> # declare -A A=([a:b]=0)
> # echo ${PARAM:${A[a:b]}}
> -bash: ${A[a: bad substitution
> 
> It seems that the issue is in the use of skiparith in verify_substring_values.  Switching to to skip_to_delim removes this issue.  The ${parameter/pattern/string} expansion uses skip_to_delim to search for the second '/' so I suspect it's use is appropriate here as well.

It's not quite that simple.  The reason skiparith() is used is that
arithmetic expressions may contain a colon (test?exp1:exp2), so skiparith
skips over one colon for each `?'.  I will have to figure out a way to
continue to support this syntax for backwards compatibility and allow for
colons in other contexts.

Chet
-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
		 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/

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Substring expansion error when offset contains a colon grishalevit@gmail.com - 2015-10-19 00:45 -0700
  Re: Substring expansion error when offset contains a colon Chet Ramey <chet.ramey@case.edu> - 2015-10-26 09:19 -0400

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