Hi, Try this,

while(<DATA>){
s/\]([ATCG]*)\[/'N' x length($1)/e;
print $_;

}
__DATA__
TG[CCC]CC[TTT]
TG[CCC][TTT]
TG[CCAAATTT]

Respective Output is:

TG[CCCNNTTT]
TG[CCCTTT]
TG[CCAAATTT]

[download]

Updated: monkfan, Try below code for your second question.

while(<DATA>){
s/\]([ATCG]*)\[/my $a = $1; $a =~ s![^C]+!'N' x length($1)!e; $a/e;
print $_;
}
__DATA__
TG[CCC]CC[TTT]

Respective Output is:
TG[CCCCCTTT]

[download]

Regards,
Velusamy R.

eval"print uc\"\\c$_\""for split'','j)@,/6%@0%2,`e@3!-9v2)/@|6%,53!-9@2~j';

In reply to Re^2: Quantified Regex Replacement by Samy_rio
in thread Quantified Regex Replacement by monkfan

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