It can be done in one s/// operation...

use v5.10;
use strict;
use warnings;

$_ = '--BBB----BB--B-------B--B--BBBB---B--';

s ((B+|.)) {
    state $char = 'i';
    if (index($1, 'B') == 0) {
        $char = $char eq 'i' ? 'o' : 'i';
        'M' x length($1);
    }
    else {
        $char;
    }
}eg;

say;

[download]
use Moops; class Cow :rw { has name => (default => 'Ermintrude') }; say Cow->new->name

In reply to Re^2: Tips on how to perform this substitution? by tobyink
in thread Tips on how to perform this substitution? by Anonymous Monk

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