I definitely recommend taking an in-depth look at perlretut.

For your current issue, I would use a regex that matches the beginning of a string (^) followed by 2 of any character (.{2}) and then an a:

Thank you, that just made all the other stuff i had read click. Also thanks for the link, always looking for new information to inhale.

You could use substr for this:

use strict;
use warnings;

my $string = 'That string is funny!';

if ( substr( $string, 2, 1 ) eq 'a' ) {
    print 'The third character in $string is an "a".';
}
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But if you're set on a regex, the following will match a string whose third character is "a":

$string =~ /^..a/
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Thanks, i don't know why i did not think of substring. That defiantly is an option i should have considered.

You're most welcome, shealyw2!

G'day shealyw2,

index is another option:

Update: Oops! Left off the POSITION (index STR,SUBSTR,POSITION). Thanks, Ratazong. Here's an improved version.

$ perl -Mstrict -Mwarnings -E '
my $x = "abc";
say $x if index($x, "a", 2) == 2;
my $y = "cba";
say $y if index($y, "a", 2) == 2;
my $z = "aba";
say $z if index($z, "a", 2) == 2;
'
cba
aba
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$ perl -Mstrict -Mwarnings -E '
my $x = "abc";
say $x if index($x, "a") == 2;
my $y = "cba";
say $y if index($y, "a") == 2;
'
cba
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Note: index is based at zero (1st char = 0; 3rd char = 2)

Your index won't work in case there is an a before the third position, e.g. in the string aba. If you (really) want to use index, use the 3-argument-form instead:

$x = "aba";
print "$x\n" if index($x, "a", 2) == 2;
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HTH, Rata

++ Thanks Ratazong. You're absolutely correct. I've updated my node.

-- Ken