package Benchmark;

use strict;


=head1 NAME

Benchmark - benchmark running times of Perl code

=head1 SYNOPSIS

    use Benchmark qw(:all) ;

    timethis ($count, "code");

    # Use Perl code in strings...
    timethese($count, {
	'Name1' => '...code1...',
	'Name2' => '...code2...',
    });

    # ... or use subroutine references.
    timethese($count, {
	'Name1' => sub { ...code1... },
	'Name2' => sub { ...code2... },
    });

    # cmpthese can be used both ways as well
    cmpthese($count, {
	'Name1' => '...code1...',
	'Name2' => '...code2...',
    });

    cmpthese($count, {
	'Name1' => sub { ...code1... },
	'Name2' => sub { ...code2... },
    });

    # ...or in two stages
    $results = timethese($count, 
        {
	    'Name1' => sub { ...code1... },
	    'Name2' => sub { ...code2... },
        },
	'none'
    );
    cmpthese( $results ) ;

    $t = timeit($count, '...other code...')
    print "$count loops of other code took:",timestr($t),"\n";

    $t = countit($time, '...other code...')
    $count = $t->iters ;
    print "$count loops of other code took:",timestr($t),"\n";

    # enable hires wallclock timing if possible
    use Benchmark ':hireswallclock';

=head1 DESCRIPTION

The Benchmark module encapsulates a number of routines to help you
figure out how long it takes to execute some code.

timethis - run a chunk of code several times

timethese - run several chunks of code several times

cmpthese - print results of timethese as a comparison chart

timeit - run a chunk of code and see how long it goes

countit - see how many times a chunk of code runs in a given time


=head2 Methods

=over 10

=item new

Returns the current time.   Example:

    use Benchmark;
    $t0 = new Benchmark;
    # ... your code here ...
    $t1 = new Benchmark;
    $td = timediff($t1, $t0);
    print "the code took:",timestr($td),"\n";

=item debug

Enables or disable debugging by setting the C<$Benchmark::Debug> flag:

    debug Benchmark 1;
    $t = timeit(10, ' 5 ** $Global ');
    debug Benchmark 0;

=item iters

Returns the number of iterations.