path: root/gnu/usr.bin/perl/t/pragma/sub_lval.t

print "1..46\n";

BEGIN {
    chdir 't' if -d 't';
    unshift @INC, '../lib';
}

sub a : lvalue { my $a = 34; bless \$a }  # Return a temporary
sub b : lvalue { shift }

my $out = a(b());		# Check that temporaries are allowed.
print "# `$out'\nnot " unless ref $out eq 'main'; # Not reached if error.
print "ok 1\n";

my @out = grep /main/, a(b()); # Check that temporaries are allowed.
print "# `@out'\nnot " unless @out==1; # Not reached if error.
print "ok 2\n";

my $in;

# Check that we can return localized values from subroutines:

sub in : lvalue { $in = shift; }
sub neg : lvalue {  #(num_str) return num_str
    local $_ = shift;
    s/^\+/-/;
    $_;
}
in(neg("+2"));


print "# `$in'\nnot " unless $in eq '-2';
print "ok 3\n";

sub get_lex : lvalue { $in }
sub get_st : lvalue { $blah }
sub id : lvalue { shift }
sub id1 : lvalue { $_[0] }
sub inc : lvalue { ++$_[0] }

$in = 5;
$blah = 3;

get_st = 7;

print "# `$blah' ne 7\nnot " unless $blah eq 7;
print "ok 4\n";

get_lex = 7;

print "# `$in' ne 7\nnot " unless $in eq 7;
print "ok 5\n";

++get_st;

print "# `$blah' ne 8\nnot " unless $blah eq 8;
print "ok 6\n";

++get_lex;

print "# `$in' ne 8\nnot " unless $in eq 8;
print "ok 7\n";

id(get_st) = 10;

print "# `$blah' ne 10\nnot " unless $blah eq 10;
print "ok 8\n";

id(get_lex) = 10;

print "# `$in' ne 10\nnot " unless $in eq 10;
print "ok 9\n";

++id(get_st);

print "# `$blah' ne 11\nnot " unless $blah eq 11;
print "ok 10\n";

++id(get_lex);

print "# `$in' ne 11\nnot " unless $in eq 11;
print "ok 11\n";

id1(get_st) = 20;

print "# `$blah' ne 20\nnot " unless $blah eq 20;
print "ok 12\n";

id1(get_lex) = 20;

print "# `$in' ne 20\nnot " unless $in eq 20;
print "ok 13\n";

++id1(get_st);

print "# `$blah' ne 21\nnot " unless $blah eq 21;
print "ok 14\n";

++id1(get_lex);

print "# `$in' ne 21\nnot " unless $in eq 21;
print "ok 15\n";

inc(get_st);

print "# `$blah' ne 22\nnot " unless $blah eq 22;
print "ok 16\n";

inc(get_lex);

print "# `$in' ne 22\nnot " unless $in eq 22;
print "ok 17\n";

inc(id(get_st));

print "# `$blah' ne 23\nnot " unless $blah eq 23;
print "ok 18\n";

inc(id(get_lex));

print "# `$in' ne 23\nnot " unless $in eq 23;
print "ok 19\n";

++inc(id1(id(get_st)));

print "# `$blah' ne 25\nnot " unless $blah eq 25;
print "ok 20\n";

++inc(id1(id(get_lex)));

print "# `$in' ne 25\nnot " unless $in eq 25;
print "ok 21\n";

@a = (1) x 3;
@b = (undef) x 2;
$#c = 3;			# These slots are not fillable.

# Explanation: empty slots contain &sv_undef.

=for disabled constructs

sub a3 :lvalue {@a}
sub b2 : lvalue {@b}
sub c4: lvalue {@c}

$_ = '';

eval <<'EOE' or $_ = $@;
  ($x, a3, $y, b2, $z, c4, $t) = (34 .. 78);
  1;
EOE

#@out = ($x, a3, $y, b2, $z, c4, $t);
#@in = (34 .. 41, (undef) x 4, 46);
#print "# `@out' ne `@in'\nnot " unless "@out" eq "@in";

print "# '$_'.\nnot "
  unless /Can\'t return an uninitialized value from lvalue subroutine/;
=cut

print "ok 22\n";

my $var;

sub a::var : lvalue { $var }

"a"->var = 45;

print "# `$var' ne 45\nnot " unless $var eq 45;
print "ok 23\n";

my $oo;
$o = bless \$oo, "a";

$o->var = 47;

print "# `$var' ne 47\nnot " unless $var eq 47;
print "ok 24\n";

sub o : lvalue { $o }

o->var = 49;

print "# `$var' ne 49\nnot " unless $var eq 49;
print "ok 25\n";

sub nolv () { $x0, $x1 } # Not lvalue

$_ = '';

eval <<'EOE' or $_ = $@;
  nolv = (2,3);
  1;
EOE

print "not "
  unless /Can\'t modify non-lvalue subroutine call in scalar assignment/;
print "ok 26\n";

$_ = '';

eval <<'EOE' or $_ = $@;
  nolv = (2,3) if $_;
  1;
EOE

print "not "
  unless /Can\'t modify non-lvalue subroutine call in scalar assignment/;
print "ok 27\n";

$_ = '';

eval <<'EOE' or $_ = $@;
  &nolv = (2,3) if $_;
  1;
EOE

print "not "
  unless /Can\'t modify non-lvalue subroutine call in scalar assignment/;
print "ok 28\n";

$x0 = $x1 = $_ = undef;
$nolv = \&nolv;

eval <<'EOE' or $_ = $@;
  $nolv->() = (2,3) if $_;
  1;
EOE

print "# '$_', '$x0', '$x1'.\nnot " if defined $_;
print "ok 29\n";

$x0 = $x1 = $_ = undef;
$nolv = \&nolv;

eval <<'EOE' or $_ = $@;
  $nolv->() = (2,3);
  1;
EOE

print "# '$_', '$x0', '$x1'.\nnot "
  unless /Can\'t modify non-lvalue subroutine call/;
print "ok 30\n";

sub lv0 : lvalue { }		# Converted to lv10 in scalar context

$_ = undef;
eval <<'EOE' or $_ = $@;
  lv0 = (2,3);
  1;
EOE

print "# '$_'.\nnot "
  unless /Can\'t return a readonly value from lvalue subroutine/;
print "ok 31\n";

sub lv10 : lvalue {}

$_ = undef;
eval <<'EOE' or $_ = $@;
  (lv0) = (2,3);
  1;
EOE

print "# '$_'.\nnot " if defined $_;
print "ok 32\n";

sub lv1u :lvalue { undef }

$_ = undef;
eval <<'EOE' or $_ = $@;
  lv1u = (2,3);
  1;
EOE

print "# '$_'.\nnot "
  unless /Can\'t return a readonly value from lvalue subroutine/;
print "ok 33\n";

$_ = undef;
eval <<'EOE' or $_ = $@;
  (lv1u) = (2,3);
  1;
EOE

print "# '$_'.\nnot "
  unless /Can\'t return an uninitialized value from lvalue subroutine/;
print "ok 34\n";

$x = '1234567';
sub lv1t : lvalue { index $x, 2 }

$_ = undef;
eval <<'EOE' or $_ = $@;
  lv1t = (2,3);
  1;
EOE

print "# '$_'.\nnot "
  unless /Can\'t return a temporary from lvalue subroutine/;
print "ok 35\n";

$_ = undef;
eval <<'EOE' or $_ = $@;
  (lv1t) = (2,3);
  1;
EOE

print "# '$_'.\nnot "
  unless /Can\'t return a temporary from lvalue subroutine/;
print "ok 36\n";

$xxx = 'xxx';
sub xxx () { $xxx }  # Not lvalue
sub lv1tmp : lvalue { xxx }			# is it a TEMP?

$_ = undef;
eval <<'EOE' or $_ = $@;
  lv1tmp = (2,3);
  1;
EOE

print "# '$_'.\nnot "
  unless /Can\'t return a temporary from lvalue subroutine/;
print "ok 37\n";

$_ = undef;
eval <<'EOE' or $_ = $@;
  (lv1tmp) = (2,3);
  1;
EOE

print "# '$_'.\nnot "
  unless /Can\'t return a temporary from lvalue subroutine/;
print "ok 38\n";

sub xxx () { 'xxx' } # Not lvalue
sub lv1tmpr : lvalue { xxx }			# is it a TEMP?

$_ = undef;
eval <<'EOE' or $_ = $@;
  lv1tmpr = (2,3);
  1;
EOE

print "# '$_'.\nnot "
  unless /Can\'t return a readonly value from lvalue subroutine/;
print "ok 39\n";

$_ = undef;
eval <<'EOE' or $_ = $@;
  (lv1tmpr) = (2,3);
  1;
EOE

print "# '$_'.\nnot "
  unless /Can\'t return a readonly value from lvalue subroutine/;
print "ok 40\n";

=for disabled constructs

sub lva : lvalue {@a}

$_ = undef;
@a = ();
$a[1] = 12;
eval <<'EOE' or $_ = $@;
  (lva) = (2,3);
  1;
EOE

print "# '$_'.\nnot "
  unless /Can\'t return an uninitialized value from lvalue subroutine/;
print "ok 41\n";

$_ = undef;
@a = ();
$a[0] = undef;
$a[1] = 12;
eval <<'EOE' or $_ = $@;
  (lva) = (2,3);
  1;
EOE

print "# '$_'.\nnot " unless "'@a' $_" eq "'2 3' ";
print "ok 42\n";

$_ = undef;
@a = ();
$a[0] = undef;
$a[1] = 12;
eval <<'EOE' or $_ = $@;
  (lva) = (2,3);
  1;
EOE

print "# '$_'.\nnot " unless "'@a' $_" eq "'2 3' ";
print "ok 43\n";

=cut

print "ok $_\n" for 41..43;

sub lv1n : lvalue { $newvar }

$_ = undef;
eval <<'EOE' or $_ = $@;
  lv1n = (3,4);
  1;
EOE

print "# '$_', '$newvar'.\nnot " unless "'$newvar' $_" eq "'4' ";
print "ok 44\n";

sub lv1nn : lvalue { $nnewvar }

$_ = undef;
eval <<'EOE' or $_ = $@;
  (lv1nn) = (3,4);
  1;
EOE

print "# '$_'.\nnot " unless "'$nnewvar' $_" eq "'3' ";
print "ok 45\n";

$a = \&lv1nn;
$a->() = 8;
print "# '$nnewvar'.\nnot " unless $nnewvar eq '8';
print "ok 46\n";