Grep regex matches, groups


 
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# 1  
Old 06-18-2009
Lightbulb Grep regex matches, groups

Hello,

I am searching all over the place for this, just not finding anything solid Smilie

I want to do be able to access the groups that are matched with grep (either with extended regex, or perl compatible regex). For instance:

Code:
echo "abcd" | egrep "a(b(c(d)))"

Of course this returns "abcd", but I would like to have access to each regex group that matched as well. In just bash, I believe there is a SUBMATCH array, but it seems to not be set in this case.

Any help would be greatly appreciated! Thanks!!
# 2  
Old 06-18-2009
I think you have to use perl or awk:
Code:
perl -ne '$,=" ... "; chomp; /a(b(c(d)))/ && print $_,$&,$1,$2,$3,"\n";'

The output in order is : the line that matched, the text that matched the entire regexp, the first (outermost) group, the second, group, the third group, (newline).
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