xref: /openbsd/gnu/usr.bin/perl/t/op/lop.t (revision fc61954a) 
1#!./perl
2
3#
4# test the logical operators '&&', '||', '!', 'and', 'or', 'not'
5#
6
7BEGIN {
8    chdir 't' if -d 't';
9    @INC = '../lib';
10    require './test.pl';
11}
12
13plan tests => 17;
14
15for my $i (undef, 0 .. 2, "", "0 but true") {
16    my $true = 1;
17    my $false = 0;
18    for my $j (undef, 0 .. 2, "", "0 but true") {
19	$true &&= !(
20	    ((!$i || !$j) != !($i && $j))
21	    or (!($i || $j) != (!$i && !$j))
22	    or (!!($i || $j) != !(!$i && !$j))
23	    or (!(!$i || !$j) != !!($i && $j))
24	);
25	$false ||= (
26	    ((!$i || !$j) == !!($i && $j))
27	    and (!!($i || $j) == (!$i && !$j))
28	    and ((!$i || $j) == ($i && !$j))
29	    and (($i || !$j) != (!$i && $j))
30	);
31    }
32    my $m = ! defined $i ? 'undef'
33       : $i eq ''   ? 'empty string'
34       : $i;
35    ok( $true, "true: $m");
36    ok( ! $false, "false: $m");
37}
38
39my $i = 0;
40(($i ||= 1) &&= 3) += 4;
41is( $i, 7, '||=, &&=');
42
43my ($x, $y) = (1, 8);
44$i = !$x || $y;
45is( $i, 8, 'negation precedence with ||' );
46
47++$y;
48$i = !$x || !$x || !$x || $y;
49is( $i, 9, 'negation precedence with ||, multiple operands' );
50
51$x = 0;
52++$y;
53$i = !$x && $y;
54is( $i, 10, 'negation precedence with &&' );
55
56++$y;
57$i = !$x && !$x && !$x && $y;
58is( $i, 11, 'negation precedence with &&, multiple operands' );
59