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#!./perl

BEGIN {
    unless (-d 'blib') {
	chdir 't' if -d 't';
	@INC = '../lib';
	require Config; import Config;
	keys %Config; # Silence warning
	if ($Config{extensions} !~ /\bList\/Util\b/) {
	    print "1..0 # Skip: List::Util was not built\n";
	    exit 0;
	}
    }
}

use Test::More tests => 6;

use List::Util qw(sum);

my $v = sum;
is( $v,	undef,	'no args');

$v = sum(9);
is( $v, 9, 'one arg');

$v = sum(1,2,3,4);
is( $v, 10, '4 args');

$v = sum(-1);
is( $v, -1, 'one -1');

my $x = -3;

$v = sum($x, 3);
is( $v, 0, 'variable arg');

$v = sum(-3.5,3);
is( $v, -0.5, 'real numbers');