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#!./perl
BEGIN {
chdir 't';
require './test.pl';
set_up_inc("../lib");
}
push @subs, sub :const{$_} for 1..10;
is join(" ", map &$_, @subs), "1 2 3 4 5 6 7 8 9 10",
':const capturing global $_';
my $x = 3;
my $sub = sub : const { $x };
$x++;
is &$sub, 3, ':const capturing lexical';
$x = 3;
$sub = sub : const { $x+5 };
$x++;
is &$sub, 8, ':const capturing expression';
is &{sub () : const { 42 }}, 42, ':const with truly constant sub';
*foo = $sub;
{
use warnings 'redefine';
my $w;
local $SIG{__WARN__} = sub { $w .= shift };
*foo = sub (){};
like $w, qr/^Constant subroutine main::foo redefined at /,
':const subs are constant';
}
eval 'sub bar : const';
like $@, qr/^:const is not permitted on named subroutines at /,
':const on named stub';
eval 'sub baz : const { }';
like $@, qr/^:const is not permitted on named subroutines at /,
':const on named sub';
done_testing;