I tried the following back reference:
use utf8;
my $str = "725-275 is an entry - and will be at 423-569 -but- not at 0
+12-457."; 
$str =~ s/(\d{3})-(\d{3})/\1\_\2/g;

print "$str\n"

[download]
which produced the following result: 
725_275 is an entry - and will be at 423_569 -but- not at 012_457.

[download]

I am getting some strange characters if I use \x{2014}! I am not sure about the hyphen to dash substitution. Update: I just saw ikegami's reply!

In reply to Re: match substitution by umasuresh
in thread match substitution by ShayShay

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