Here is a fun (and powerful) way to only do some substitutions: 

my $str= "1_abc/2_def/bla_30_31_blah";
my $count= 0;
while(  $str =~ /\d+_/g  ) {
    last   if  2 < ++$count;
    $str =~ s///;
}
print "\$str=($str)\n";
# $str=(abc/def/bla_30_31_blah)

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Though I'd probably use one of the other solutions mentioned in this particular case.

        - tye (but my friends call me "Tye")

In reply to (tye)Re: changing only the first two matches of a regex by tye
in thread changing only the first two matches of a regex by Anonymous Monk

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