module Benchmark-0.1;
use v6;

sub timeit ($count, $code is copy) is export {
    $code = eval "sub \{ $code \}" unless $code.isa("Code");
    # TODO: handle count too low case.
    return _time_func( _loop_func($count, $code) )
	   »-« # overhead
	   _time_func( _loop_func($count, -> {}) );
}

sub _loop_func ($count, $code) {
    return sub {
	for (1..$count) {
	    $code.();
	}
    }
}

sub _time_func ($loop) {
    my @s = (time, times);
    $loop.();
    return (time, times) »-« @s;
}

sub timethese ($count, $hash) is export {
    for %$hash.kv -> $name, $code {
        my @time = timeit($count, $code);
        say "$name: { @time[0] != 0 ?? $count / @time[0] :: "Inf" } / s";
    }
}

=pod

=head1 NAME

Benchmark - Benchmark running time of Perl 6 code

=head1 SYNOPSIS

    #!/usr/bin/pugs
    use v6;
    use Benchmark;

    @t = timeit($count, 'code');
    @t = timeit($count, { 1 + 1 });

    timethese($count, { hyper => { my @r = @a >>+<< @b },
                        normal => {
			  my @r = gather {
                            take(@a[$_] + @b[$_]) for 0..@a.end;
                          }
		         }
                       });

=head1 TODO

many

=cut

=head1 AUTHOR

Chia-liang Kao, E<lt>clkao@clkao.orgE<gt>

=head1 COPYRIGHT

Copyright (c) 2005. Chia-liang Kao. All rights reserved.

This program is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.

See http://www.perl.com/perl/misc/Artistic.html

=cut