#! perl -slw
use strict;
use Readonly;
use Benchmark qw[ cmpthese ];

use constant {
    SUBSTITUTES =>       { # substitute these
        'DUTCH'       => 'NETHERLANDS',
        'GERMANY'     => 'DEUTSCHLAND',
        'AUST.'       => 'AUSTRALIA',
    },
    SKIPWORDS => { # skip these
        'BANK'        => 1,
        'CORP'        => 1,
        'GOVERNMENT'  => 1,
        'GOVT'        => 1,
        'LIMITED'     => 1,
        'LTD'         => 1,
        'NPV'         => 1,
        'COM'         => 1,
   },
};

sub wordsConstant {
  return [
    map {
        SUBSTITUTES->{$_} or $_
    } grep {
        !SKIPWORDS->{$_}
    } split /\s+/, shift ];
}

Readonly::Hash
    my %SUBSTITUTES => (
        'DUTCH'       => 'NETHERLANDS',
        'GERMANY'     => 'DEUTSCHLAND',
        'AUST.'       => 'AUSTRALIA',
);

Readonly::Hash
    my %SKIPWORDS => (
        'BANK'        => 1,
        'CORP'        => 1,
        'GOVERNMENT'  => 1,
        'GOVT'        => 1,
        'LIMITED'     => 1,
        'LTD'         => 1,
        'NPV'         => 1,
        'COM'         => 1,
);

sub wordsReadonly {
  return [
    map {
        $SUBSTITUTES{$_} or $_
    } grep {
        ! $SKIPWORDS{$_}
    } split /\s+/, shift ];
}

sub wordsInline {
  return [
    map {
      { # substitute these
        'DUTCH'       => 'NETHERLANDS',
        'GERMANY'     => 'DEUTSCHLAND',
        'AUST.'       => 'AUSTRALIA',
      }->{$_}
        or
      $_
    }
    grep {
      !{ # skip these
        'BANK'        => 1,
        'CORP'        => 1,
        'GOVERNMENT'  => 1,
        'GOVT'        => 1,
        'LIMITED'     => 1,
        'LTD'         => 1,
        'NPV'         => 1,
        'COM'         => 1,
      }->{$_}
    } split /\s+/, shift ];
}

our $testData = uc <<'EOD';
The quick dutch fox jumps over the lazy government dog.
The quick german fox jumps over the lazy bank dog.
The quick aust. fox limited jumps over the lazy corporate dog corp.
EOD

cmpthese -1, {
    constant => q[ wordsConstant( $testData ) ],
    inline   => q[ wordsInline( $testData ) ],
    readonly => q[ wordsReadonly( $testData ) ],
};

__END__
C:\test>559911
            Rate readonly   inline constant
readonly  2133/s       --     -22%     -81%
inline    2745/s      29%       --     -75%
constant 10957/s     414%     299%       --