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#!./perl
# $RCSfile: cond.t,v $$Revision: 4.1 $$Date: 92/08/07 18:27:41 $
print "1..16\n";
print 1 ? "ok 1\n" : "not ok 1\n"; # compile time
print 0 ? "not ok 2\n" : "ok 2\n";
$x = 1;
print $x ? "ok 3\n" : "not ok 3\n"; # run time
print !$x ? "not ok 4\n" : "ok 4\n";
# Very low precedence between the ? and the :
print $x ? "ok 5\n" or "not ok 5\n" : "not ok 5\n";
# Binds tighter than assignment
$msg = "not ok 6\n" ? "ok 6\n" : "ok 6\n";
print $msg;
# Binds looser than ".."
print "ok ", $x ? 7 : -2..15, "\n";
# Right-associative
print $x ? "ok 8\n" : 0 ? "not ok 8\n" : "not ok 8\n";
# No parens needed when nested like an if-elsif-elsif-elsif-else
$n = 9;
print $n == 7 ? "not ok 9\n" :
$n == 8 ? "not ok 9\n" :
$n == 9 ? "ok 9\n" :
$n == 10 ? "not ok 9\n" :
"not ok 9\n";
# Nor when used like a deeply nested if-else chain
print $n != 7 ?
$n != 8 ?
$n != 9 ?
$n != 10 ?
"not ok 10\n"
:
"not ok 10\n"
:
"ok 10\n"
:
"not ok 10\n"
:
"not ok 10\n";
# A random pathologically nested example, which parses like
# $a ? ($b ? ($c ? $d : ($e ? $f : $g)) : $h) : ($i ? $j : $k),
# i.e.,
# if ($a) {
# if ($b) {
# if ($c) {
# $d;
# } else {
# if ($e) {
# $f;
# } else {
# $g;
# }
# }
# } else {
# $h;
# }
# } else {
# if ($i) {
# $j;
# } else {
# $k;
# }
# }
# We exercise all the branches. The ".5"s should be dont-cares.
($d, $f, $g, $h, $j, $k) =
("ok 11\n", "ok 12\n", "ok 13\n", "ok 14\n", "ok 15\n", "ok 16\n");
($a, $b, $c, $e, $i) = (1, 1, 1, .5, .5);
print $a ? $ b ? $c ? $d : $e ? $f : $g : $h : $i ? $j : $k;
($a, $b, $c, $e, $i) = (1, 1, 0, 1, .5);
print $a ? $ b ? $c ? $d : $e ? $f : $g : $h : $i ? $j : $k;
($a, $b, $c, $e, $i) = (1, 1, 0, 0, .5);
print $a ? $ b ? $c ? $d : $e ? $f : $g : $h : $i ? $j : $k;
($a, $b, $c, $e, $i) = (1, 0, .5, .5, .5);
print $a ? $ b ? $c ? $d : $e ? $f : $g : $h : $i ? $j : $k;
($a, $b, $c, $e, $i) = (0, .5, .5, .5, 1);
print $a ? $ b ? $c ? $d : $e ? $f : $g : $h : $i ? $j : $k;
($a, $b, $c, $e, $i) = (0, .5, .5, .5, 0);
print $a ? $ b ? $c ? $d : $e ? $f : $g : $h : $i ? $j : $k;
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