Dear all,
I'm trying to extract a DNA sequence out of a larger string, i.e. the
string is of the following structure:
$string = "/NOTNEEDED/*ACGACGGGTTCAAGGCAG*/NOTNEEDED/"
But when I do
$string =~ /[ACGT]/;
it matches only the last letter, i.e. "G". Why doesn't it start at the
beginning?
But it gets even better, I figured that adding the greedy * should help:
$string =~ /[ACGT]*/;
and now it doesn't match anything. Shouldn't it try to match as many
times as possible?
My confusion was complete when I tried
$string =~ /[ACGT]{5}/;
now it matches 5 letters, but this time from the beginning, i.e.: ACGAC.
I fail to understand that behaviour. I checked the Perl documentation a
bit and I sort of understand why /[ACGT]/ only matches one letter only
(but not why it starts at the end). However, I'm simply puzzled at the
other things.
Thank you for your help!
Florian
