Some might consider using split and an index. The problem with this solution is that it's really slow, particularly as the string gets longer.

Here's some benchmarking code that'll show you: 

#!/usr/local/bin/perl -w
use strict;

use Benchmark;

use vars qw/$str/;

$str = "123456789asgdjlaskjglkajblnlbnlaqjteoijqotijwojgl;akjglkj";

timethese(shift || 10000, {
    'unpack' => sub { my $char = getn_unpack($str, 30) },
    'substr' => sub { my $char = getn_substr($str, 30) },
    'split'  => sub { my $char = getn_split($str, 30) }
});

sub getn_unpack {
    return unpack "x" . ($_[1]-1) . "a", $_[0];
}

sub getn_substr {
    return substr $_[0], $_[1]-1, 1;
}

sub getn_split {
    return +(split //, $_[0])[$_[1]-1];
}

[download]
And here are the benchmark results: 
Benchmark: timing 100000 iterations of split, substr, unpack...
     split: 20 secs (19.39 usr  0.00 sys = 19.39 cpu)
    substr:  0 secs ( 1.78 usr  0.00 sys =  1.78 cpu)
    unpack:  2 secs ( 2.89 usr  0.00 sys =  2.89 cpu)

[download]
The substr method is, obviously, the fastest, because that's what it's designed to do, basically.

unpack is also quite fast.
split has to split the entire string, construct an array of length($str) elements, then take an index.

So, the best way is to use substr.

In reply to Re: How do I get the Nth Character of a String? by btrott
in thread How do I get the Nth Character of a String? by vroom

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