Yes, sorry, I copied-pasted it from the actual code, hence the two different variable names...
I changed it a bit:
if($str=~/([ATCG])\.+$/)
{
    $last_mapped_char=$1;
    $rightmost_position_of_letter = rindex($str, $last_mapped_char)+1;
}

[download]

and now I think it is more sensible (at least to me). The problem I would have with the solution kindly provided above is that I would always need to compare the 4 values and find the largest one (because I only care about the last found A,T,G or C (does not matter which), before the dots start.

In reply to Re^4: Proper usage of rindex function? by Anonymous Monk
in thread Proper usage of rindex function? by Anonymous Monk

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