Re: Masking part of a string

[ferreira]

I could not resist giving a functional and expensive solution to the problem with pairwise function from List::MoreUtils.

my $mask = '001111100';
my $str  = 'AGACGAGTA';

my @mask = split( '', $mask );
my @str  = split( '', $str );
my $masked = join '', pairwise { $a ? 'x' : $b } @mask, @str;

print "Masked: $masked\n";

And now using regexes:

my $mask = '001111100';
my $str  = 'AGACGAGTA';

my $masked = '';
while ( $mask =~ /\G(.)/gc ) { # walk the mask
    my $bit = $1;
    if ( $str =~ /\G(.)/gc ) { # walk the string to be masked
        $masked .= $bit ? 'x' : $1;
    }
}

print "Masked: $masked\n";

Probably it could be improved in space if mask is represented as a bit vector and there is an iterator to walk the mask just like $mask =~ /\G(.)/gc is doing.