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

use constant {
    TRUE => 1,
    FALSE => 0,
    VALUE => 12345,
};

use Readonly;

Readonly::Scalar my $true => 1;
Readonly::Scalar my $false => 0;
Readonly::Scalar my $value => 12345;


sub usingConstant {
    for( 1 .. 1e6 ) {
        if( TRUE ) {
            my $sum = VALUE * VALUE;
        }
        if( FALSE ) {
            ;## Never called
        }
    }
}

sub usingLiterals {
    for( 1 .. 1e6 ) {
        if( 1 ) {
            my $sum = 12345 * 12345;
        }
        if( 0 ) {
            ;## Never called
        }
    }
}

sub usingReadonly {
    for( 1 .. 1e6 ) {
        if( $true ) {
            my $sum = $value * $value;
        }
        if( $false ) {
            ;## Never called
        }
    }
}

cmpthese -1, {
    const    => sub{ usingConstant() },
    literals => sub{ usingLiterals() },
    Readonly => sub{ usingReadonly() },
};