G'day lakssreedhar,

You haven't actually asked a question - please take a look at: How do I post a question effectively?

For the scenario you describe, I'd be looking at a positive look-behind assertion - see perlre - Extended Patterns for details.

Here's an example: 

$ perl -Mstrict -Mwarnings -E '
my @words = qw{door name dad naming};
for (@words) {
    s{(?<=na)m}{+d};
    say;
}
'
door
na+de
dad
na+ding

[download]

-- Ken

In reply to Re: replace a character based on rule file by kcott
in thread replace a character based on rule file by lakssreedhar

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