Try:

...
if ($string =~ /^[ATGC]{8}$/) {
...

[download]

Note the caret and dollar-sign. This should match sequences that are exactly eight characters long.


What can be asserted without proof can be dismissed without proof. - Christopher Hitchens, 1949-2011

In reply to Re: Why doesn't quantifier work with character classes? by thezip
in thread Why doesn't quantifier work with character classes? by rnaeye

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