I'm not clear about what you want.
How is this?:

#!/usr/bin/perl
use strict;
use warnings;

my $str = 'hello nr34 , 56, hi';
print "input string=$str\n";

$str =~ s/.*nr(\d+)([^\d]+)(\d+)(.*)/"calc(nr$1)$2".eval{$3*4}."$4";/e
+;
print "output string=$str\n";

__END__
Prints:
input string=hello nr34 , 56, hi
output string=calc(nr34) , 224, hi

[download]
Please give some more example lines.
I doubt that the above solves the "problem".

In reply to Re: String substitution by Marshall
in thread String substitution by kepler

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