An alternative approach to reading the first character of a string:

    $char = chr ord $string;
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This is mainly of curiosity value since it would be better in terms of legibility and maintenance to use one of the more standard methods shown below. In particular substr.

Interestingly, albeit moderately, this appears to be faster than some of the other methods.

    #!/usr/bin/perl -w

    use strict;

    use Benchmark 'cmpthese';

    my $str = "some string here";


    cmpthese( 500000, {
               'pop_chord' => sub { pop_chord($str) },
               '_substr'   => sub { _substr($str)   },
               '_unpack'   => sub { _unpack($str)   },
               '_match'    => sub { _match($str)    },
              }
        );


    sub pop_chord {
        chr ord pop
    }

    sub _substr {
        substr pop,0,1
    }

    sub _unpack {
        unpack"a",pop
    }

    sub _match {
        (pop=~/(.)/s)[0]
    }


    __END__


    Benchmark:
    timing 500000 iterations of _match, _substr, _unpack, pop_chord

        _match:  3 secs (3.22 usr + 0.01 sys = 3.23 CPU) @ 154798.76/s

       _substr:  0 secs (0.85 usr + 0.00 sys = 0.85 CPU) @ 588235.29/s

       _unpack:  2 secs (2.04 usr + 0.00 sys = 2.04 CPU) @ 245098.04/s

     pop_chord:  1 secs (0.73 usr + 0.00 sys = 0.73 CPU) @ 684931.51/s

                  Rate    _match   _unpack   _substr pop_chord
    _match    154799/s        --      -37%      -74%      -77%
    _unpack   245098/s       58%        --      -58%      -64%
    _substr   588235/s      280%      140%        --      -14%
    pop_chord 684932/s      342%      179%       16%        --
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