xref: /openbsd-src/gnu/usr.bin/perl/lib/overload.t (revision 2b0358df1d88d06ef4139321dd05bd5e05d91eaf)
1#!./perl
2
3BEGIN {
4    chdir 't' if -d 't';
5    @INC = '../lib';
6    require Config;
7    if (($Config::Config{'extensions'} !~ m!\bList/Util\b!) ){
8	print "1..0 # Skip -- Perl configured without List::Util module\n";
9	exit 0;
10    }
11}
12
13package Oscalar;
14use overload (
15				# Anonymous subroutines:
16'+'	=>	sub {new Oscalar $ {$_[0]}+$_[1]},
17'-'	=>	sub {new Oscalar
18		       $_[2]? $_[1]-${$_[0]} : ${$_[0]}-$_[1]},
19'<=>'	=>	sub {new Oscalar
20		       $_[2]? $_[1]-${$_[0]} : ${$_[0]}-$_[1]},
21'cmp'	=>	sub {new Oscalar
22		       $_[2]? ($_[1] cmp ${$_[0]}) : (${$_[0]} cmp $_[1])},
23'*'	=>	sub {new Oscalar ${$_[0]}*$_[1]},
24'/'	=>	sub {new Oscalar
25		       $_[2]? $_[1]/${$_[0]} :
26			 ${$_[0]}/$_[1]},
27'%'	=>	sub {new Oscalar
28		       $_[2]? $_[1]%${$_[0]} : ${$_[0]}%$_[1]},
29'**'	=>	sub {new Oscalar
30		       $_[2]? $_[1]**${$_[0]} : ${$_[0]}-$_[1]},
31
32qw(
33""	stringify
340+	numify)			# Order of arguments insignificant
35);
36
37sub new {
38  my $foo = $_[1];
39  bless \$foo, $_[0];
40}
41
42sub stringify { "${$_[0]}" }
43sub numify { 0 + "${$_[0]}" }	# Not needed, additional overhead
44				# comparing to direct compilation based on
45				# stringify
46
47package main;
48
49$| = 1;
50use Test::More tests => 556;
51
52
53$a = new Oscalar "087";
54$b= "$a";
55
56is($b, $a);
57is($b, "087");
58is(ref $a, "Oscalar");
59is($a, $a);
60is($a, "087");
61
62$c = $a + 7;
63
64is(ref $c, "Oscalar");
65isnt($c, $a);
66is($c, "94");
67
68$b=$a;
69
70is(ref $a, "Oscalar");
71
72$b++;
73
74is(ref $b, "Oscalar");
75is($a, "087");
76is($b, "88");
77is(ref $a, "Oscalar");
78
79$c=$b;
80$c-=$a;
81
82is(ref $c, "Oscalar");
83is($a, "087");
84is($c, "1");
85is(ref $a, "Oscalar");
86
87$b=1;
88$b+=$a;
89
90is(ref $b, "Oscalar");
91is($a, "087");
92is($b, "88");
93is(ref $a, "Oscalar");
94
95eval q[ package Oscalar; use overload ('++' => sub { $ {$_[0]}++;$_[0] } ) ];
96
97$b=$a;
98
99is(ref $a, "Oscalar");
100
101$b++;
102
103is(ref $b, "Oscalar");
104is($a, "087");
105is($b, "88");
106is(ref $a, "Oscalar");
107
108package Oscalar;
109$dummy=bless \$dummy;		# Now cache of method should be reloaded
110package main;
111
112$b=$a;
113$b++;
114
115is(ref $b, "Oscalar");
116is($a, "087");
117is($b, "88");
118is(ref $a, "Oscalar");
119
120undef $b;			# Destroying updates tables too...
121
122eval q[package Oscalar; use overload ('++' => sub { $ {$_[0]} += 2; $_[0] } ) ];
123
124$b=$a;
125
126is(ref $a, "Oscalar");
127
128$b++;
129
130is(ref $b, "Oscalar");
131is($a, "087");
132is($b, "88");
133is(ref $a, "Oscalar");
134
135package Oscalar;
136$dummy=bless \$dummy;		# Now cache of method should be reloaded
137package main;
138
139$b++;
140
141is(ref $b, "Oscalar");
142is($a, "087");
143is($b, "90");
144is(ref $a, "Oscalar");
145
146$b=$a;
147$b++;
148
149is(ref $b, "Oscalar");
150is($a, "087");
151is($b, "89");
152is(ref $a, "Oscalar");
153
154
155ok($b? 1:0);
156
157eval q[ package Oscalar; use overload ('=' => sub {$main::copies++;
158						   package Oscalar;
159						   local $new=$ {$_[0]};
160						   bless \$new } ) ];
161
162$b=new Oscalar "$a";
163
164is(ref $b, "Oscalar");
165is($a, "087");
166is($b, "087");
167is(ref $a, "Oscalar");
168
169$b++;
170
171is(ref $b, "Oscalar");
172is($a, "087");
173is($b, "89");
174is(ref $a, "Oscalar");
175is($copies, undef);
176
177$b+=1;
178
179is(ref $b, "Oscalar");
180is($a, "087");
181is($b, "90");
182is(ref $a, "Oscalar");
183is($copies, undef);
184
185$b=$a;
186$b+=1;
187
188is(ref $b, "Oscalar");
189is($a, "087");
190is($b, "88");
191is(ref $a, "Oscalar");
192is($copies, undef);
193
194$b=$a;
195$b++;
196
197is(ref $b, "Oscalar");
198is($a, "087");
199is($b, "89");
200is(ref $a, "Oscalar");
201is($copies, 1);
202
203eval q[package Oscalar; use overload ('+=' => sub {$ {$_[0]} += 3*$_[1];
204						   $_[0] } ) ];
205$c=new Oscalar;			# Cause rehash
206
207$b=$a;
208$b+=1;
209
210is(ref $b, "Oscalar");
211is($a, "087");
212is($b, "90");
213is(ref $a, "Oscalar");
214is($copies, 2);
215
216$b+=$b;
217
218is(ref $b, "Oscalar");
219is($b, "360");
220is($copies, 2);
221$b=-$b;
222
223is(ref $b, "Oscalar");
224is($b, "-360");
225is($copies, 2);
226
227$b=abs($b);
228
229is(ref $b, "Oscalar");
230is($b, "360");
231is($copies, 2);
232
233$b=abs($b);
234
235is(ref $b, "Oscalar");
236is($b, "360");
237is($copies, 2);
238
239eval q[package Oscalar;
240       use overload ('x' => sub {new Oscalar ( $_[2] ? "_.$_[1]._" x $ {$_[0]}
241					      : "_.${$_[0]}._" x $_[1])}) ];
242
243$a=new Oscalar "yy";
244$a x= 3;
245is($a, "_.yy.__.yy.__.yy._");
246
247eval q[package Oscalar;
248       use overload ('.' => sub {new Oscalar ( $_[2] ?
249					      "_.$_[1].__.$ {$_[0]}._"
250					      : "_.$ {$_[0]}.__.$_[1]._")}) ];
251
252$a=new Oscalar "xx";
253
254is("b${a}c", "_._.b.__.xx._.__.c._");
255
256# Check inheritance of overloading;
257{
258  package OscalarI;
259  @ISA = 'Oscalar';
260}
261
262$aI = new OscalarI "$a";
263is(ref $aI, "OscalarI");
264is("$aI", "xx");
265is($aI, "xx");
266is("b${aI}c", "_._.b.__.xx._.__.c._");
267
268# Here we test blessing to a package updates hash
269
270eval "package Oscalar; no overload '.'";
271
272is("b${a}", "_.b.__.xx._");
273$x="1";
274bless \$x, Oscalar;
275is("b${a}c", "bxxc");
276new Oscalar 1;
277is("b${a}c", "bxxc");
278
279# Negative overloading:
280
281$na = eval { ~$a };
282like($@, qr/no method found/);
283
284# Check AUTOLOADING:
285
286*Oscalar::AUTOLOAD =
287  sub { *{"Oscalar::$AUTOLOAD"} = sub {"_!_" . shift() . "_!_"} ;
288	goto &{"Oscalar::$AUTOLOAD"}};
289
290eval "package Oscalar; sub comple; use overload '~' => 'comple'";
291
292$na = eval { ~$a };		# Hash was not updated
293like($@, qr/no method found/);
294
295bless \$x, Oscalar;
296
297$na = eval { ~$a };		# Hash updated
298warn "`$na', $@" if $@;
299ok !$@;
300is($na, '_!_xx_!_');
301
302$na = 0;
303
304$na = eval { ~$aI };		# Hash was not updated
305like($@, qr/no method found/);
306
307bless \$x, OscalarI;
308
309$na = eval { ~$aI };
310print $@;
311
312ok(!$@);
313is($na, '_!_xx_!_');
314
315eval "package Oscalar; sub rshft; use overload '>>' => 'rshft'";
316
317$na = eval { $aI >> 1 };	# Hash was not updated
318like($@, qr/no method found/);
319
320bless \$x, OscalarI;
321
322$na = 0;
323
324$na = eval { $aI >> 1 };
325print $@;
326
327ok(!$@);
328is($na, '_!_xx_!_');
329
330# warn overload::Method($a, '0+'), "\n";
331is(overload::Method($a, '0+'), \&Oscalar::numify);
332is(overload::Method($aI,'0+'), \&Oscalar::numify);
333ok(overload::Overloaded($aI));
334ok(!overload::Overloaded('overload'));
335
336ok(! defined overload::Method($aI, '<<'));
337ok(! defined overload::Method($a, '<'));
338
339like (overload::StrVal($aI), qr/^OscalarI=SCALAR\(0x[\da-fA-F]+\)$/);
340is(overload::StrVal(\$aI), "@{[\$aI]}");
341
342# Check overloading by methods (specified deep in the ISA tree).
343{
344  package OscalarII;
345  @ISA = 'OscalarI';
346  sub Oscalar::lshft {"_<<_" . shift() . "_<<_"}
347  eval "package OscalarI; use overload '<<' => 'lshft', '|' => 'lshft'";
348}
349
350$aaII = "087";
351$aII = \$aaII;
352bless $aII, 'OscalarII';
353bless \$fake, 'OscalarI';		# update the hash
354is(($aI | 3), '_<<_xx_<<_');
355# warn $aII << 3;
356is(($aII << 3), '_<<_087_<<_');
357
358{
359  BEGIN { $int = 7; overload::constant 'integer' => sub {$int++; shift}; }
360  $out = 2**10;
361}
362is($int, 9);
363is($out, 1024);
364
365$foo = 'foo';
366$foo1 = 'f\'o\\o';
367{
368  BEGIN { $q = $qr = 7; 
369	  overload::constant 'q' => sub {$q++; push @q, shift, ($_[1] || 'none'); shift},
370			     'qr' => sub {$qr++; push @qr, shift, ($_[1] || 'none'); shift}; }
371  $out = 'foo';
372  $out1 = 'f\'o\\o';
373  $out2 = "a\a$foo,\,";
374  /b\b$foo.\./;
375}
376
377is($out, 'foo');
378is($out, $foo);
379is($out1, 'f\'o\\o');
380is($out1, $foo1);
381is($out2, "a\afoo,\,");
382is("@q", "foo q f'o\\\\o q a\\a qq ,\\, qq");
383is($q, 11);
384is("@qr", "b\\b qq .\\. qq");
385is($qr, 9);
386
387{
388  $_ = '!<b>!foo!<-.>!';
389  BEGIN { overload::constant 'q' => sub {push @q1, shift, ($_[1] || 'none'); "_<" . (shift) . ">_"},
390			     'qr' => sub {push @qr1, shift, ($_[1] || 'none'); "!<" . (shift) . ">!"}; }
391  $out = 'foo';
392  $out1 = 'f\'o\\o';
393  $out2 = "a\a$foo,\,";
394  $res = /b\b$foo.\./;
395  $a = <<EOF;
396oups
397EOF
398  $b = <<'EOF';
399oups1
400EOF
401  $c = bareword;
402  m'try it';
403  s'first part'second part';
404  s/yet another/tail here/;
405  tr/A-Z/a-z/;
406}
407
408is($out, '_<foo>_');
409is($out1, '_<f\'o\\o>_');
410is($out2, "_<a\a>_foo_<,\,>_");
411is("@q1", "foo q f'o\\\\o q a\\a qq ,\\, qq oups
412 qq oups1
413 q second part q tail here s A-Z tr a-z tr");
414is("@qr1", "b\\b qq .\\. qq try it q first part q yet another qq");
415is($res, 1);
416is($a, "_<oups
417>_");
418is($b, "_<oups1
419>_");
420is($c, "bareword");
421
422{
423  package symbolic;		# Primitive symbolic calculator
424  use overload nomethod => \&wrap, '""' => \&str, '0+' => \&num,
425      '=' => \&cpy, '++' => \&inc, '--' => \&dec;
426
427  sub new { shift; bless ['n', @_] }
428  sub cpy {
429    my $self = shift;
430    bless [@$self], ref $self;
431  }
432  sub inc { $_[0] = bless ['++', $_[0], 1]; }
433  sub dec { $_[0] = bless ['--', $_[0], 1]; }
434  sub wrap {
435    my ($obj, $other, $inv, $meth) = @_;
436    if ($meth eq '++' or $meth eq '--') {
437      @$obj = ($meth, (bless [@$obj]), 1); # Avoid circular reference
438      return $obj;
439    }
440    ($obj, $other) = ($other, $obj) if $inv;
441    bless [$meth, $obj, $other];
442  }
443  sub str {
444    my ($meth, $a, $b) = @{+shift};
445    $a = 'u' unless defined $a;
446    if (defined $b) {
447      "[$meth $a $b]";
448    } else {
449      "[$meth $a]";
450    }
451  } 
452  my %subr = ( 'n' => sub {$_[0]} );
453  foreach my $op (split " ", $overload::ops{with_assign}) {
454    $subr{$op} = $subr{"$op="} = eval "sub {shift() $op shift()}";
455  }
456  my @bins = qw(binary 3way_comparison num_comparison str_comparison);
457  foreach my $op (split " ", "@overload::ops{ @bins }") {
458    $subr{$op} = eval "sub {shift() $op shift()}";
459  }
460  foreach my $op (split " ", "@overload::ops{qw(unary func)}") {
461    $subr{$op} = eval "sub {$op shift()}";
462  }
463  $subr{'++'} = $subr{'+'};
464  $subr{'--'} = $subr{'-'};
465  
466  sub num {
467    my ($meth, $a, $b) = @{+shift};
468    my $subr = $subr{$meth} 
469      or die "Do not know how to ($meth) in symbolic";
470    $a = $a->num if ref $a eq __PACKAGE__;
471    $b = $b->num if ref $b eq __PACKAGE__;
472    $subr->($a,$b);
473  }
474  sub TIESCALAR { my $pack = shift; $pack->new(@_) }
475  sub FETCH { shift }
476  sub nop {  }		# Around a bug
477  sub vars { my $p = shift; tie($_, $p), $_->nop foreach @_; }
478  sub STORE { 
479    my $obj = shift; 
480    $#$obj = 1; 
481    $obj->[1] = shift;
482  }
483}
484
485{
486  my $foo = new symbolic 11;
487  my $baz = $foo++;
488  is((sprintf "%d", $foo), '12');
489  is((sprintf "%d", $baz), '11');
490  my $bar = $foo;
491  $baz = ++$foo;
492  is((sprintf "%d", $foo), '13');
493  is((sprintf "%d", $bar), '12');
494  is((sprintf "%d", $baz), '13');
495  my $ban = $foo;
496  $baz = ($foo += 1);
497  is((sprintf "%d", $foo), '14');
498  is((sprintf "%d", $bar), '12');
499  is((sprintf "%d", $baz), '14');
500  is((sprintf "%d", $ban), '13');
501  $baz = 0;
502  $baz = $foo++;
503  is((sprintf "%d", $foo), '15');
504  is((sprintf "%d", $baz), '14');
505  is("$foo", '[++ [+= [++ [++ [n 11] 1] 1] 1] 1]');
506}
507
508{
509  my $iter = new symbolic 2;
510  my $side = new symbolic 1;
511  my $cnt = $iter;
512  
513  while ($cnt) {
514    $cnt = $cnt - 1;		# The "simple" way
515    $side = (sqrt(1 + $side**2) - 1)/$side;
516  }
517  my $pi = $side*(2**($iter+2));
518  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
519  is((sprintf "%f", $pi), '3.182598');
520}
521
522{
523  my $iter = new symbolic 2;
524  my $side = new symbolic 1;
525  my $cnt = $iter;
526  
527  while ($cnt--) {
528    $side = (sqrt(1 + $side**2) - 1)/$side;
529  }
530  my $pi = $side*(2**($iter+2));
531  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
532  is((sprintf "%f", $pi), '3.182598');
533}
534
535{
536  my ($a, $b);
537  symbolic->vars($a, $b);
538  my $c = sqrt($a**2 + $b**2);
539  $a = 3; $b = 4;
540  is((sprintf "%d", $c), '5');
541  $a = 12; $b = 5;
542  is((sprintf "%d", $c), '13');
543}
544
545{
546  package symbolic1;		# Primitive symbolic calculator
547  # Mutator inc/dec
548  use overload nomethod => \&wrap, '""' => \&str, '0+' => \&num, '=' => \&cpy;
549
550  sub new { shift; bless ['n', @_] }
551  sub cpy {
552    my $self = shift;
553    bless [@$self], ref $self;
554  }
555  sub wrap {
556    my ($obj, $other, $inv, $meth) = @_;
557    if ($meth eq '++' or $meth eq '--') {
558      @$obj = ($meth, (bless [@$obj]), 1); # Avoid circular reference
559      return $obj;
560    }
561    ($obj, $other) = ($other, $obj) if $inv;
562    bless [$meth, $obj, $other];
563  }
564  sub str {
565    my ($meth, $a, $b) = @{+shift};
566    $a = 'u' unless defined $a;
567    if (defined $b) {
568      "[$meth $a $b]";
569    } else {
570      "[$meth $a]";
571    }
572  } 
573  my %subr = ( 'n' => sub {$_[0]} );
574  foreach my $op (split " ", $overload::ops{with_assign}) {
575    $subr{$op} = $subr{"$op="} = eval "sub {shift() $op shift()}";
576  }
577  my @bins = qw(binary 3way_comparison num_comparison str_comparison);
578  foreach my $op (split " ", "@overload::ops{ @bins }") {
579    $subr{$op} = eval "sub {shift() $op shift()}";
580  }
581  foreach my $op (split " ", "@overload::ops{qw(unary func)}") {
582    $subr{$op} = eval "sub {$op shift()}";
583  }
584  $subr{'++'} = $subr{'+'};
585  $subr{'--'} = $subr{'-'};
586  
587  sub num {
588    my ($meth, $a, $b) = @{+shift};
589    my $subr = $subr{$meth} 
590      or die "Do not know how to ($meth) in symbolic";
591    $a = $a->num if ref $a eq __PACKAGE__;
592    $b = $b->num if ref $b eq __PACKAGE__;
593    $subr->($a,$b);
594  }
595  sub TIESCALAR { my $pack = shift; $pack->new(@_) }
596  sub FETCH { shift }
597  sub nop {  }		# Around a bug
598  sub vars { my $p = shift; tie($_, $p), $_->nop foreach @_; }
599  sub STORE { 
600    my $obj = shift; 
601    $#$obj = 1; 
602    $obj->[1] = shift;
603  }
604}
605
606{
607  my $foo = new symbolic1 11;
608  my $baz = $foo++;
609  is((sprintf "%d", $foo), '12');
610  is((sprintf "%d", $baz), '11');
611  my $bar = $foo;
612  $baz = ++$foo;
613  is((sprintf "%d", $foo), '13');
614  is((sprintf "%d", $bar), '12');
615  is((sprintf "%d", $baz), '13');
616  my $ban = $foo;
617  $baz = ($foo += 1);
618  is((sprintf "%d", $foo), '14');
619  is((sprintf "%d", $bar), '12');
620  is((sprintf "%d", $baz), '14');
621  is((sprintf "%d", $ban), '13');
622  $baz = 0;
623  $baz = $foo++;
624  is((sprintf "%d", $foo), '15');
625  is((sprintf "%d", $baz), '14');
626  is("$foo", '[++ [+= [++ [++ [n 11] 1] 1] 1] 1]');
627}
628
629{
630  my $iter = new symbolic1 2;
631  my $side = new symbolic1 1;
632  my $cnt = $iter;
633  
634  while ($cnt) {
635    $cnt = $cnt - 1;		# The "simple" way
636    $side = (sqrt(1 + $side**2) - 1)/$side;
637  }
638  my $pi = $side*(2**($iter+2));
639  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
640  is((sprintf "%f", $pi), '3.182598');
641}
642
643{
644  my $iter = new symbolic1 2;
645  my $side = new symbolic1 1;
646  my $cnt = $iter;
647  
648  while ($cnt--) {
649    $side = (sqrt(1 + $side**2) - 1)/$side;
650  }
651  my $pi = $side*(2**($iter+2));
652  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
653  is((sprintf "%f", $pi), '3.182598');
654}
655
656{
657  my ($a, $b);
658  symbolic1->vars($a, $b);
659  my $c = sqrt($a**2 + $b**2);
660  $a = 3; $b = 4;
661  is((sprintf "%d", $c), '5');
662  $a = 12; $b = 5;
663  is((sprintf "%d", $c), '13');
664}
665
666{
667  package two_face;		# Scalars with separate string and
668                                # numeric values.
669  sub new { my $p = shift; bless [@_], $p }
670  use overload '""' => \&str, '0+' => \&num, fallback => 1;
671  sub num {shift->[1]}
672  sub str {shift->[0]}
673}
674
675{
676  my $seven = new two_face ("vii", 7);
677  is((sprintf "seven=$seven, seven=%d, eight=%d", $seven, $seven+1),
678	'seven=vii, seven=7, eight=8');
679  is(scalar ($seven =~ /i/), '1');
680}
681
682{
683  package sorting;
684  use overload 'cmp' => \&comp;
685  sub new { my ($p, $v) = @_; bless \$v, $p }
686  sub comp { my ($x,$y) = @_; ($$x * 3 % 10) <=> ($$y * 3 % 10) or $$x cmp $$y }
687}
688{
689  my @arr = map sorting->new($_), 0..12;
690  my @sorted1 = sort @arr;
691  my @sorted2 = map $$_, @sorted1;
692  is("@sorted2", '0 10 7 4 1 11 8 5 12 2 9 6 3');
693}
694{
695  package iterator;
696  use overload '<>' => \&iter;
697  sub new { my ($p, $v) = @_; bless \$v, $p }
698  sub iter { my ($x) = @_; return undef if $$x < 0; return $$x--; }
699}
700
701# XXX iterator overload not intended to work with CORE::GLOBAL?
702if (defined &CORE::GLOBAL::glob) {
703  is('1', '1');
704  is('1', '1');
705  is('1', '1');
706}
707else {
708  my $iter = iterator->new(5);
709  my $acc = '';
710  my $out;
711  $acc .= " $out" while $out = <${iter}>;
712  is($acc, ' 5 4 3 2 1 0');
713  $iter = iterator->new(5);
714  is(scalar <${iter}>, '5');
715  $acc = '';
716  $acc .= " $out" while $out = <$iter>;
717  is($acc, ' 4 3 2 1 0');
718}
719{
720  package deref;
721  use overload '%{}' => \&hderef, '&{}' => \&cderef, 
722    '*{}' => \&gderef, '${}' => \&sderef, '@{}' => \&aderef;
723  sub new { my ($p, $v) = @_; bless \$v, $p }
724  sub deref {
725    my ($self, $key) = (shift, shift);
726    my $class = ref $self;
727    bless $self, 'deref::dummy'; # Disable overloading of %{} 
728    my $out = $self->{$key};
729    bless $self, $class;	# Restore overloading
730    $out;
731  }
732  sub hderef {shift->deref('h')}
733  sub aderef {shift->deref('a')}
734  sub cderef {shift->deref('c')}
735  sub gderef {shift->deref('g')}
736  sub sderef {shift->deref('s')}
737}
738{
739  my $deref = bless { h => { foo => 5 , fake => 23 },
740		      c => sub {return shift() + 34},
741		      's' => \123,
742		      a => [11..13],
743		      g => \*srt,
744		    }, 'deref';
745  # Hash:
746  my @cont = sort %$deref;
747  if ("\t" eq "\011") { # ASCII
748      is("@cont", '23 5 fake foo');
749  } 
750  else {                # EBCDIC alpha-numeric sort order
751      is("@cont", 'fake foo 23 5');
752  }
753  my @keys = sort keys %$deref;
754  is("@keys", 'fake foo');
755  my @val = sort values %$deref;
756  is("@val", '23 5');
757  is($deref->{foo}, 5);
758  is(defined $deref->{bar}, '');
759  my $key;
760  @keys = ();
761  push @keys, $key while $key = each %$deref;
762  @keys = sort @keys;
763  is("@keys", 'fake foo');
764  is(exists $deref->{bar}, '');
765  is(exists $deref->{foo}, 1);
766  # Code:
767  is($deref->(5), 39);
768  is(&$deref(6), 40);
769  sub xxx_goto { goto &$deref }
770  is(xxx_goto(7), 41);
771  my $srt = bless { c => sub {$b <=> $a}
772		  }, 'deref';
773  *srt = \&$srt;
774  my @sorted = sort srt 11, 2, 5, 1, 22;
775  is("@sorted", '22 11 5 2 1');
776  # Scalar
777  is($$deref, 123);
778  # Code
779  @sorted = sort $srt 11, 2, 5, 1, 22;
780  is("@sorted", '22 11 5 2 1');
781  # Array
782  is("@$deref", '11 12 13');
783  is($#$deref, '2');
784  my $l = @$deref;
785  is($l, 3);
786  is($deref->[2], '13');
787  $l = pop @$deref;
788  is($l, 13);
789  $l = 1;
790  is($deref->[$l], '12');
791  # Repeated dereference
792  my $double = bless { h => $deref,
793		     }, 'deref';
794  is($double->{foo}, 5);
795}
796
797{
798  package two_refs;
799  use overload '%{}' => \&gethash, '@{}' => sub { ${shift()} };
800  sub new { 
801    my $p = shift; 
802    bless \ [@_], $p;
803  }
804  sub gethash {
805    my %h;
806    my $self = shift;
807    tie %h, ref $self, $self;
808    \%h;
809  }
810
811  sub TIEHASH { my $p = shift; bless \ shift, $p }
812  my %fields;
813  my $i = 0;
814  $fields{$_} = $i++ foreach qw{zero one two three};
815  sub STORE { 
816    my $self = ${shift()};
817    my $key = $fields{shift()};
818    defined $key or die "Out of band access";
819    $$self->[$key] = shift;
820  }
821  sub FETCH { 
822    my $self = ${shift()};
823    my $key = $fields{shift()};
824    defined $key or die "Out of band access";
825    $$self->[$key];
826  }
827}
828
829my $bar = new two_refs 3,4,5,6;
830$bar->[2] = 11;
831is($bar->{two}, 11);
832$bar->{three} = 13;
833is($bar->[3], 13);
834
835{
836  package two_refs_o;
837  @ISA = ('two_refs');
838}
839
840$bar = new two_refs_o 3,4,5,6;
841$bar->[2] = 11;
842is($bar->{two}, 11);
843$bar->{three} = 13;
844is($bar->[3], 13);
845
846{
847  package two_refs1;
848  use overload '%{}' => sub { ${shift()}->[1] },
849               '@{}' => sub { ${shift()}->[0] };
850  sub new { 
851    my $p = shift; 
852    my $a = [@_];
853    my %h;
854    tie %h, $p, $a;
855    bless \ [$a, \%h], $p;
856  }
857  sub gethash {
858    my %h;
859    my $self = shift;
860    tie %h, ref $self, $self;
861    \%h;
862  }
863
864  sub TIEHASH { my $p = shift; bless \ shift, $p }
865  my %fields;
866  my $i = 0;
867  $fields{$_} = $i++ foreach qw{zero one two three};
868  sub STORE { 
869    my $a = ${shift()};
870    my $key = $fields{shift()};
871    defined $key or die "Out of band access";
872    $a->[$key] = shift;
873  }
874  sub FETCH { 
875    my $a = ${shift()};
876    my $key = $fields{shift()};
877    defined $key or die "Out of band access";
878    $a->[$key];
879  }
880}
881
882$bar = new two_refs_o 3,4,5,6;
883$bar->[2] = 11;
884is($bar->{two}, 11);
885$bar->{three} = 13;
886is($bar->[3], 13);
887
888{
889  package two_refs1_o;
890  @ISA = ('two_refs1');
891}
892
893$bar = new two_refs1_o 3,4,5,6;
894$bar->[2] = 11;
895is($bar->{two}, 11);
896$bar->{three} = 13;
897is($bar->[3], 13);
898
899{
900  package B;
901  use overload bool => sub { ${+shift} };
902}
903
904my $aaa;
905{ my $bbbb = 0; $aaa = bless \$bbbb, B }
906
907is !$aaa, 1;
908
909unless ($aaa) {
910  pass();
911} else {
912  fail();
913}
914
915# check that overload isn't done twice by join
916{ my $c = 0;
917  package Join;
918  use overload '""' => sub { $c++ };
919  my $x = join '', bless([]), 'pq', bless([]);
920  main::is $x, '0pq1';
921};
922
923# Test module-specific warning
924{
925    # check the Odd number of arguments for overload::constant warning
926    my $a = "" ;
927    local $SIG{__WARN__} = sub {$a = $_[0]} ;
928    $x = eval ' overload::constant "integer" ; ' ;
929    is($a, "");
930    use warnings 'overload' ;
931    $x = eval ' overload::constant "integer" ; ' ;
932    like($a, qr/^Odd number of arguments for overload::constant at/);
933}
934
935{
936    # check the `$_[0]' is not an overloadable type warning
937    my $a = "" ;
938    local $SIG{__WARN__} = sub {$a = $_[0]} ;
939    $x = eval ' overload::constant "fred" => sub {} ; ' ;
940    is($a, "");
941    use warnings 'overload' ;
942    $x = eval ' overload::constant "fred" => sub {} ; ' ;
943    like($a, qr/^`fred' is not an overloadable type at/);
944}
945
946{
947    # check the `$_[1]' is not a code reference warning
948    my $a = "" ;
949    local $SIG{__WARN__} = sub {$a = $_[0]} ;
950    $x = eval ' overload::constant "integer" => 1; ' ;
951    is($a, "");
952    use warnings 'overload' ;
953    $x = eval ' overload::constant "integer" => 1; ' ;
954    like($a, qr/^`1' is not a code reference at/);
955}
956
957{
958  my $c = 0;
959  package ov_int1;
960  use overload '""'    => sub { 3+shift->[0] },
961               '0+'    => sub { 10+shift->[0] },
962               'int'   => sub { 100+shift->[0] };
963  sub new {my $p = shift; bless [shift], $p}
964
965  package ov_int2;
966  use overload '""'    => sub { 5+shift->[0] },
967               '0+'    => sub { 30+shift->[0] },
968               'int'   => sub { 'ov_int1'->new(1000+shift->[0]) };
969  sub new {my $p = shift; bless [shift], $p}
970
971  package noov_int;
972  use overload '""'    => sub { 2+shift->[0] },
973               '0+'    => sub { 9+shift->[0] };
974  sub new {my $p = shift; bless [shift], $p}
975
976  package main;
977
978  my $x = new noov_int 11;
979  my $int_x = int $x;
980  main::is("$int_x", 20);
981  $x = new ov_int1 31;
982  $int_x = int $x;
983  main::is("$int_x", 131);
984  $x = new ov_int2 51;
985  $int_x = int $x;
986  main::is("$int_x", 1054);
987}
988
989# make sure that we don't infinitely recurse
990{
991  my $c = 0;
992  package Recurse;
993  use overload '""'    => sub { shift },
994               '0+'    => sub { shift },
995               'bool'  => sub { shift },
996               fallback => 1;
997  my $x = bless([]);
998  # For some reason beyond me these have to be oks rather than likes.
999  main::ok("$x" =~ /Recurse=ARRAY/);
1000  main::ok($x);
1001  main::ok($x+0 =~ qr/Recurse=ARRAY/);
1002}
1003
1004# BugID 20010422.003
1005package Foo;
1006
1007use overload
1008  'bool' => sub { return !$_[0]->is_zero() || undef; }
1009;
1010 
1011sub is_zero
1012  {
1013  my $self = shift;
1014  return $self->{var} == 0;
1015  }
1016
1017sub new
1018  {
1019  my $class = shift;
1020  my $self =  {};
1021  $self->{var} = shift;
1022  bless $self,$class;
1023  }
1024
1025package main;
1026
1027use strict;
1028
1029my $r = Foo->new(8);
1030$r = Foo->new(0);
1031
1032is(($r || 0), 0);
1033
1034package utf8_o;
1035
1036use overload 
1037  '""'  =>  sub { return $_[0]->{var}; }
1038  ;
1039  
1040sub new
1041  {
1042    my $class = shift;
1043    my $self =  {};
1044    $self->{var} = shift;
1045    bless $self,$class;
1046  }
1047
1048package main;
1049
1050
1051my $utfvar = new utf8_o 200.2.1;
1052is("$utfvar", 200.2.1); # 223 - stringify
1053is("a$utfvar", "a".200.2.1); # 224 - overload via sv_2pv_flags
1054
1055# 225..227 -- more %{} tests.  Hangs in 5.6.0, okay in later releases.
1056# Basically this example implements strong encapsulation: if Hderef::import()
1057# were to eval the overload code in the caller's namespace, the privatisation
1058# would be quite transparent.
1059package Hderef;
1060use overload '%{}' => sub { (caller(0))[0] eq 'Foo' ? $_[0] : die "zap" };
1061package Foo;
1062@Foo::ISA = 'Hderef';
1063sub new { bless {}, shift }
1064sub xet { @_ == 2 ? $_[0]->{$_[1]} :
1065	  @_ == 3 ? ($_[0]->{$_[1]} = $_[2]) : undef }
1066package main;
1067my $a = Foo->new;
1068$a->xet('b', 42);
1069is ($a->xet('b'), 42);
1070ok (!defined eval { $a->{b} });
1071like ($@, qr/zap/);
1072
1073{
1074   package t229;
1075   use overload '='  => sub { 42 },
1076                '++' => sub { my $x = ${$_[0]}; $_[0] };
1077   sub new { my $x = 42; bless \$x }
1078
1079   my $warn;
1080   {  
1081     local $SIG{__WARN__} = sub { $warn++ };
1082      my $x = t229->new;
1083      my $y = $x;
1084      eval { $y++ };
1085   }
1086   main::ok (!$warn);
1087}
1088
1089{
1090    my ($int, $out1, $out2);
1091    {
1092        BEGIN { $int = 0; overload::constant 'integer' => sub {$int++; 17}; }
1093        $out1 = 0;
1094        $out2 = 1;
1095    }
1096    is($int,  2,  "#24313");	# 230
1097    is($out1, 17, "#24313");	# 231
1098    is($out2, 17, "#24313");	# 232
1099}
1100
1101{
1102    package Numify;
1103    use overload (qw(0+ numify fallback 1));
1104
1105    sub new {
1106	my $val = $_[1];
1107	bless \$val, $_[0];
1108    }
1109
1110    sub numify { ${$_[0]} }
1111}
1112
1113{
1114    package perl31793;
1115    use overload cmp => sub { 0 };
1116    package perl31793_fb;
1117    use overload cmp => sub { 0 }, fallback => 1;
1118    package main;
1119    my $o  = bless [], 'perl31793';
1120    my $of = bless [], 'perl31793_fb';
1121    my $no = bless [], 'no_overload';
1122    like(overload::StrVal(\"scalar"), qr/^SCALAR\(0x[0-9a-f]+\)$/);
1123    like(overload::StrVal([]),        qr/^ARRAY\(0x[0-9a-f]+\)$/);
1124    like(overload::StrVal({}),        qr/^HASH\(0x[0-9a-f]+\)$/);
1125    like(overload::StrVal(sub{1}),    qr/^CODE\(0x[0-9a-f]+\)$/);
1126    like(overload::StrVal(\*GLOB),    qr/^GLOB\(0x[0-9a-f]+\)$/);
1127    like(overload::StrVal(\$o),       qr/^REF\(0x[0-9a-f]+\)$/);
1128    like(overload::StrVal(qr/a/),     qr/^Regexp=SCALAR\(0x[0-9a-f]+\)$/);
1129    like(overload::StrVal($o),        qr/^perl31793=ARRAY\(0x[0-9a-f]+\)$/);
1130    like(overload::StrVal($of),       qr/^perl31793_fb=ARRAY\(0x[0-9a-f]+\)$/);
1131    like(overload::StrVal($no),       qr/^no_overload=ARRAY\(0x[0-9a-f]+\)$/);
1132}
1133
1134# These are all check that overloaded values rather than reference addresses
1135# are what is getting tested.
1136my ($two, $one, $un, $deux) = map {new Numify $_} 2, 1, 1, 2;
1137my ($ein, $zwei) = (1, 2);
1138
1139my %map = (one => 1, un => 1, ein => 1, deux => 2, two => 2, zwei => 2);
1140foreach my $op (qw(<=> == != < <= > >=)) {
1141    foreach my $l (keys %map) {
1142	foreach my $r (keys %map) {
1143	    my $ocode = "\$$l $op \$$r";
1144	    my $rcode = "$map{$l} $op $map{$r}";
1145
1146	    my $got = eval $ocode;
1147	    die if $@;
1148	    my $expect = eval $rcode;
1149	    die if $@;
1150	    is ($got, $expect, $ocode) or print "# $rcode\n";
1151	}
1152    }
1153}
1154{
1155    # check that overloading works in regexes
1156    {
1157	package Foo493;
1158	use overload
1159	    '""' => sub { "^$_[0][0]\$" },
1160	    '.'  => sub { 
1161		    bless [
1162			     $_[2]
1163			    ? (ref $_[1] ? $_[1][0] : $_[1]) . ':' .$_[0][0] 
1164			    : $_[0][0] . ':' . (ref $_[1] ? $_[1][0] : $_[1])
1165		    ], 'Foo493'
1166			};
1167    }
1168
1169    my $a = bless [ "a" ], 'Foo493';
1170    like('a', qr/$a/);
1171    like('x:a', qr/x$a/);
1172    like('x:a:=', qr/x$a=$/);
1173    like('x:a:a:=', qr/x$a$a=$/);
1174
1175}
1176
1177{
1178    my $twenty_three = 23;
1179    # Check that constant overloading propagates into evals
1180    BEGIN { overload::constant integer => sub { 23 } }
1181    is(eval "17", $twenty_three);
1182}
1183
1184{
1185    package Sklorsh;
1186    use overload
1187	bool     => sub { shift->is_cool };
1188
1189    sub is_cool {
1190	$_[0]->{name} eq 'cool';
1191    }
1192
1193    sub delete {
1194	undef %{$_[0]};
1195	bless $_[0], 'Brap';
1196	return 1;
1197    }
1198
1199    sub delete_with_self {
1200	my $self = shift;
1201	undef %$self;
1202	bless $self, 'Brap';
1203	return 1;
1204    }
1205
1206    package Brap;
1207
1208    1;
1209
1210    package main;
1211
1212    my $obj;
1213    $obj = bless {name => 'cool'}, 'Sklorsh';
1214    $obj->delete;
1215    ok(eval {if ($obj) {1}; 1}, $@ || 'reblessed into nonexistent namespace');
1216
1217    $obj = bless {name => 'cool'}, 'Sklorsh';
1218    $obj->delete_with_self;
1219    ok (eval {if ($obj) {1}; 1}, $@);
1220    
1221    my $a = $b = {name => 'hot'};
1222    bless $b, 'Sklorsh';
1223    is(ref $a, 'Sklorsh');
1224    is(ref $b, 'Sklorsh');
1225    ok(!$b, "Expect overloaded boolean");
1226    ok(!$a, "Expect overloaded boolean");
1227}
1228{
1229    use Scalar::Util 'weaken';
1230
1231    package Shklitza;
1232    use overload '""' => sub {"CLiK KLAK"};
1233
1234    package Ksshfwoom;
1235
1236    package main;
1237
1238    my ($obj, $ref);
1239    $obj = bless do {my $a; \$a}, 'Shklitza';
1240    $ref = $obj;
1241
1242    is ($obj, "CLiK KLAK");
1243    is ($ref, "CLiK KLAK");
1244
1245    weaken $ref;
1246    is ($ref, "CLiK KLAK");
1247
1248    bless $obj, 'Ksshfwoom';
1249
1250    like ($obj, qr/^Ksshfwoom=/);
1251    like ($ref, qr/^Ksshfwoom=/);
1252
1253    undef $obj;
1254    is ($ref, undef);
1255}
1256
1257{
1258    package bit;
1259    # bit operations have overloadable assignment variants too
1260
1261    sub new { bless \$_[1], $_[0] }
1262
1263    use overload
1264          "&=" => sub { bit->new($_[0]->val . ' & ' . $_[1]->val) }, 
1265          "^=" => sub { bit->new($_[0]->val . ' ^ ' . $_[1]->val) },
1266          "|"  => sub { bit->new($_[0]->val . ' | ' . $_[1]->val) }, # |= by fallback
1267          ;
1268
1269    sub val { ${$_[0]} }
1270
1271    package main;
1272
1273    my $a = bit->new(my $va = 'a');
1274    my $b = bit->new(my $vb = 'b');
1275
1276    $a &= $b;
1277    is($a->val, 'a & b', "overloaded &= works");
1278
1279    my $c = bit->new(my $vc = 'c');
1280
1281    $b ^= $c;
1282    is($b->val, 'b ^ c', "overloaded ^= works");
1283
1284    my $d = bit->new(my $vd = 'd');
1285
1286    $c |= $d;
1287    is($c->val, 'c | d', "overloaded |= (by fallback) works");
1288}
1289
1290{
1291    # comparison operators with nomethod
1292    my $warning = "";
1293    my $method;
1294
1295    package nomethod_false;
1296    use overload nomethod => sub { $method = 'nomethod'; 0 };
1297
1298    package nomethod_true;
1299    use overload nomethod => sub { $method= 'nomethod'; 'true' };
1300
1301    package main;
1302    local $^W = 1;
1303    local $SIG{__WARN__} = sub { $warning = $_[0] };
1304
1305    my $f = bless [], 'nomethod_false';
1306    ($warning, $method) = ("", "");
1307    is($f eq 'whatever', 0, 'nomethod makes eq return 0');
1308    is($method, 'nomethod');
1309
1310    my $t = bless [], 'nomethod_true';
1311    ($warning, $method) = ("", "");
1312    is($t eq 'whatever', 'true', 'nomethod makes eq return "true"');
1313    is($method, 'nomethod');
1314    is($warning, "", 'nomethod eq need not return number');
1315
1316    eval q{ 
1317        package nomethod_false;
1318        use overload cmp => sub { $method = 'cmp'; 0 };
1319    };
1320    $f = bless [], 'nomethod_false';
1321    ($warning, $method) = ("", "");
1322    ok($f eq 'whatever', 'eq falls back to cmp (nomethod not called)');
1323    is($method, 'cmp');
1324
1325    eval q{
1326        package nomethod_true;
1327        use overload cmp => sub { $method = 'cmp'; 'true' };
1328    };
1329    $t = bless [], 'nomethod_true';
1330    ($warning, $method) = ("", "");
1331    ok($t eq 'whatever', 'eq falls back to cmp (nomethod not called)');
1332    is($method, 'cmp');
1333    like($warning, qr/isn't numeric/, 'cmp should return number');
1334
1335}
1336
1337{
1338    # Subtle bug pre 5.10, as a side effect of the overloading flag being
1339    # stored on the reference rather than the referent. Despite the fact that
1340    # objects can only be accessed via references (even internally), the
1341    # referent actually knows that it's blessed, not the references. So taking
1342    # a new, unrelated, reference to it gives an object. However, the
1343    # overloading-or-not flag was on the reference prior to 5.10, and taking
1344    # a new reference didn't (use to) copy it.
1345
1346    package kayo;
1347
1348    use overload '""' => sub {${$_[0]}};
1349
1350    sub Pie {
1351	return "$_[0], $_[1]";
1352    }
1353
1354    package main;
1355
1356    my $class = 'kayo';
1357    my $string = 'bam';
1358    my $crunch_eth = bless \$string, $class;
1359
1360    is("$crunch_eth", $string);
1361    is ($crunch_eth->Pie("Meat"), "$string, Meat");
1362
1363    my $wham_eth = \$string;
1364
1365    is("$wham_eth", $string,
1366       'This reference did not have overloading in 5.8.8 and earlier');
1367    is ($crunch_eth->Pie("Apple"), "$string, Apple");
1368
1369    my $class = ref $wham_eth;
1370    $class =~ s/=.*//;
1371
1372    # Bless it back into its own class!
1373    bless $wham_eth, $class;
1374
1375    is("$wham_eth", $string);
1376    is ($crunch_eth->Pie("Blackbird"), "$string, Blackbird");
1377}
1378
1379{
1380    package numify_int;
1381    use overload "0+" => sub { $_[0][0] += 1; 42 };
1382    package numify_self;
1383    use overload "0+" => sub { $_[0][0]++; $_[0] };
1384    package numify_other;
1385    use overload "0+" => sub { $_[0][0]++; $_[0][1] = bless [], 'numify_int' };
1386    package numify_by_fallback;
1387    use overload fallback => 1;
1388
1389    package main;
1390    my $o = bless [], 'numify_int';
1391    is(int($o), 42, 'numifies to integer');
1392    is($o->[0], 1, 'int() numifies only once');
1393
1394    my $aref = [];
1395    my $num_val = int($aref);
1396    my $r = bless $aref, 'numify_self';
1397    is(int($r), $num_val, 'numifies to self');
1398    is($r->[0], 1, 'int() numifies once when returning self');
1399
1400    my $s = bless [], 'numify_other';
1401    is(int($s), 42, 'numifies to numification of other object');
1402    is($s->[0], 1, 'int() numifies once when returning other object');
1403    is($s->[1][0], 1, 'returned object numifies too');
1404
1405    my $m = bless $aref, 'numify_by_fallback';
1406    is(int($m), $num_val, 'numifies to usual reference value');
1407    is(abs($m), $num_val, 'numifies to usual reference value');
1408    is(-$m, -$num_val, 'numifies to usual reference value');
1409    is(0+$m, $num_val, 'numifies to usual reference value');
1410    is($m+0, $num_val, 'numifies to usual reference value');
1411    is($m+$m, 2*$num_val, 'numifies to usual reference value');
1412    is(0-$m, -$num_val, 'numifies to usual reference value');
1413    is(1*$m, $num_val, 'numifies to usual reference value');
1414    is($m/1, $num_val, 'numifies to usual reference value');
1415    is($m%100, $num_val%100, 'numifies to usual reference value');
1416    is($m**1, $num_val, 'numifies to usual reference value');
1417
1418    is(abs($aref), $num_val, 'abs() of ref');
1419    is(-$aref, -$num_val, 'negative of ref');
1420    is(0+$aref, $num_val, 'ref addition');
1421    is($aref+0, $num_val, 'ref addition');
1422    is($aref+$aref, 2*$num_val, 'ref addition');
1423    is(0-$aref, -$num_val, 'subtraction of ref');
1424    is(1*$aref, $num_val, 'multiplicaton of ref');
1425    is($aref/1, $num_val, 'division of ref');
1426    is($aref%100, $num_val%100, 'modulo of ref');
1427    is($aref**1, $num_val, 'exponentiation of ref');
1428}
1429
1430# EOF
1431