Re: how to search for a substring in a parameter?

[Peter Stephenson <pws@csr.com>]

Carlos Carvalho wrote:
> I'm trying to see if the value of a parameter contains a given string
> but didn't find an elegant way.

What was wrong with

if [[ $foo = *pattern* ]]; then
  ...

?  The patterns are identical to those in parameter substitution.

> All pattern matching substitutions
> return only the non-matched portion of the value.

You can use the flags M for the matched portion combined with either
head or tail matching using the S flag to tell it to match substrings,
i.e. anywhere in the pattern.

% foo='this is a pattern, too'
% print ${(MS)foo##pattern}
pattern

The M flag doesn't work with the `/' or `//' substitutions (and the S
flag is differnt --- it forces the shortest match).  Not clear
if that's `really' a bug, but it does agree with the documentation.

-- 
Peter Stephenson <pws@csr.com>                  Software Engineer
CSR Ltd., Science Park, Milton Road,
Cambridge, CB4 0WH, UK                          Tel: +44 (0)1223 692070


**********************************************************************
The information transmitted is intended only for the person or
entity to which it is addressed and may contain confidential 
and/or privileged material. 
Any review, retransmission, dissemination or other use of, or
taking of any action in reliance upon, this information by 
persons or entities other than the intended recipient is 
prohibited.  
If you received this in error, please contact the sender and 
delete the material from any computer.
**********************************************************************