Anonymonk's solution would look slightly better ("foo", instead of "o", if the "+" symbol was moved inside the open paren.

Anyway - here is a similar one-liner alternative: 

> perl -anF_ -e '$F[1] and chomp,push @{$h{$F[0]}},$_}{print "$_ ",sca
+lar @{$h{$_}}," ",join " ", @{$h{$_}},"\n" for sort keys %h' test.txt
bar 5 bar_1-a bar_2-a bar_3-b bar_4-a bar_5-b
foo 4 foo_1-a foo_2-b foo_3-b foo_4-b

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        "You're only given one little spark of madness. You mustn't lose it."         - Robin Williams

In reply to Re: Create a hash for each unique captured regex variable by NetWallah
in thread Create a hash for each unique captured regex variable by hkates

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