summaryrefslogtreecommitdiff
path: root/lib/overload.t
blob: d63ff4d354400155aa7a550be2c37dee09b60ed4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
#!./perl -T

BEGIN {
    chdir 't' if -d 't';
    @INC = '../lib';
    require Config;
    if (($Config::Config{'extensions'} !~ m!\bList/Util\b!) ){
	print "1..0 # Skip -- Perl configured without List::Util module\n";
	exit 0;
    }
}

package Oscalar;
use overload ( 
				# Anonymous subroutines:
'+'	=>	sub {new Oscalar $ {$_[0]}+$_[1]},
'-'	=>	sub {new Oscalar
		       $_[2]? $_[1]-${$_[0]} : ${$_[0]}-$_[1]},
'<=>'	=>	sub {new Oscalar
		       $_[2]? $_[1]-${$_[0]} : ${$_[0]}-$_[1]},
'cmp'	=>	sub {new Oscalar
		       $_[2]? ($_[1] cmp ${$_[0]}) : (${$_[0]} cmp $_[1])},
'*'	=>	sub {new Oscalar ${$_[0]}*$_[1]},
'/'	=>	sub {new Oscalar 
		       $_[2]? $_[1]/${$_[0]} :
			 ${$_[0]}/$_[1]},
'%'	=>	sub {new Oscalar
		       $_[2]? $_[1]%${$_[0]} : ${$_[0]}%$_[1]},
'**'	=>	sub {new Oscalar
		       $_[2]? $_[1]**${$_[0]} : ${$_[0]}-$_[1]},

qw(
""	stringify
0+	numify)			# Order of arguments insignificant
);

sub new {
  my $foo = $_[1];
  bless \$foo, $_[0];
}

sub stringify { "${$_[0]}" }
sub numify { 0 + "${$_[0]}" }	# Not needed, additional overhead
				# comparing to direct compilation based on
				# stringify

package main;

$| = 1;
use Test::More tests => 4880;

use Scalar::Util qw(tainted);

$a = new Oscalar "087";
$b= "$a";

is($b, $a);
is($b, "087");
is(ref $a, "Oscalar");
is($a, $a);
is($a, "087");

$c = $a + 7;

is(ref $c, "Oscalar");
isnt($c, $a);
is($c, "94");

$b=$a;

is(ref $a, "Oscalar");

$b++;

is(ref $b, "Oscalar");
is($a, "087");
is($b, "88");
is(ref $a, "Oscalar");

$c=$b;
$c-=$a;

is(ref $c, "Oscalar");
is($a, "087");
is($c, "1");
is(ref $a, "Oscalar");

$b=1;
$b+=$a;

is(ref $b, "Oscalar");
is($a, "087");
is($b, "88");
is(ref $a, "Oscalar");

eval q[ package Oscalar; use overload ('++' => sub { $ {$_[0]}++;$_[0] } ) ];

$b=$a;

is(ref $a, "Oscalar");

$b++;

is(ref $b, "Oscalar");
is($a, "087");
is($b, "88");
is(ref $a, "Oscalar");

package Oscalar;
$dummy=bless \$dummy;		# Now cache of method should be reloaded
package main;

$b=$a;
$b++;				

is(ref $b, "Oscalar");
is($a, "087");
is($b, "88");
is(ref $a, "Oscalar");

undef $b;			# Destroying updates tables too...

eval q[package Oscalar; use overload ('++' => sub { $ {$_[0]} += 2; $_[0] } ) ];

$b=$a;

is(ref $a, "Oscalar");

$b++;

is(ref $b, "Oscalar");
is($a, "087");
is($b, "88");
is(ref $a, "Oscalar");

package Oscalar;
$dummy=bless \$dummy;		# Now cache of method should be reloaded
package main;

$b++;				

is(ref $b, "Oscalar");
is($a, "087");
is($b, "90");
is(ref $a, "Oscalar");

$b=$a;
$b++;

is(ref $b, "Oscalar");
is($a, "087");
is($b, "89");
is(ref $a, "Oscalar");


ok($b? 1:0);

eval q[ package Oscalar; use overload ('=' => sub {$main::copies++; 
						   package Oscalar;
						   local $new=$ {$_[0]};
						   bless \$new } ) ];

$b=new Oscalar "$a";

is(ref $b, "Oscalar");
is($a, "087");
is($b, "087");
is(ref $a, "Oscalar");

$b++;

is(ref $b, "Oscalar");
is($a, "087");
is($b, "89");
is(ref $a, "Oscalar");
is($copies, undef);

$b+=1;

is(ref $b, "Oscalar");
is($a, "087");
is($b, "90");
is(ref $a, "Oscalar");
is($copies, undef);

$b=$a;
$b+=1;

is(ref $b, "Oscalar");
is($a, "087");
is($b, "88");
is(ref $a, "Oscalar");
is($copies, undef);

$b=$a;
$b++;

is(ref $b, "Oscalar");
is($a, "087");
is($b, "89");
is(ref $a, "Oscalar");
is($copies, 1);

eval q[package Oscalar; use overload ('+=' => sub {$ {$_[0]} += 3*$_[1];
						   $_[0] } ) ];
$c=new Oscalar;			# Cause rehash

$b=$a;
$b+=1;

is(ref $b, "Oscalar");
is($a, "087");
is($b, "90");
is(ref $a, "Oscalar");
is($copies, 2);

$b+=$b;

is(ref $b, "Oscalar");
is($b, "360");
is($copies, 2);
$b=-$b;

is(ref $b, "Oscalar");
is($b, "-360");
is($copies, 2);

$b=abs($b);

is(ref $b, "Oscalar");
is($b, "360");
is($copies, 2);

$b=abs($b);

is(ref $b, "Oscalar");
is($b, "360");
is($copies, 2);

eval q[package Oscalar; 
       use overload ('x' => sub {new Oscalar ( $_[2] ? "_.$_[1]._" x $ {$_[0]}
					      : "_.${$_[0]}._" x $_[1])}) ];

$a=new Oscalar "yy";
$a x= 3;
is($a, "_.yy.__.yy.__.yy._");

eval q[package Oscalar; 
       use overload ('.' => sub {new Oscalar ( $_[2] ? 
					      "_.$_[1].__.$ {$_[0]}._"
					      : "_.$ {$_[0]}.__.$_[1]._")}) ];

$a=new Oscalar "xx";

is("b${a}c", "_._.b.__.xx._.__.c._");

# Check inheritance of overloading;
{
  package OscalarI;
  @ISA = 'Oscalar';
}

$aI = new OscalarI "$a";
is(ref $aI, "OscalarI");
is("$aI", "xx");
is($aI, "xx");
is("b${aI}c", "_._.b.__.xx._.__.c._");

# Here we test blessing to a package updates hash

eval "package Oscalar; no overload '.'";

is("b${a}", "_.b.__.xx._");
$x="1";
bless \$x, Oscalar;
is("b${a}c", "bxxc");
new Oscalar 1;
is("b${a}c", "bxxc");

# Negative overloading:

$na = eval { ~$a };
like($@, qr/no method found/);

# Check AUTOLOADING:

*Oscalar::AUTOLOAD = 
  sub { *{"Oscalar::$AUTOLOAD"} = sub {"_!_" . shift() . "_!_"} ;
	goto &{"Oscalar::$AUTOLOAD"}};

eval "package Oscalar; sub comple; use overload '~' => 'comple'";

$na = eval { ~$a };		# Hash was not updated
like($@, qr/no method found/);

bless \$x, Oscalar;

$na = eval { ~$a };		# Hash updated
warn "`$na', $@" if $@;
ok !$@;
is($na, '_!_xx_!_');

$na = 0;

$na = eval { ~$aI };		# Hash was not updated
like($@, qr/no method found/);

bless \$x, OscalarI;

$na = eval { ~$aI };
print $@;

ok(!$@);
is($na, '_!_xx_!_');

eval "package Oscalar; sub rshft; use overload '>>' => 'rshft'";

$na = eval { $aI >> 1 };	# Hash was not updated
like($@, qr/no method found/);

bless \$x, OscalarI;

$na = 0;

$na = eval { $aI >> 1 };
print $@;

ok(!$@);
is($na, '_!_xx_!_');

# warn overload::Method($a, '0+'), "\n";
is(overload::Method($a, '0+'), \&Oscalar::numify);
is(overload::Method($aI,'0+'), \&Oscalar::numify);
ok(overload::Overloaded($aI));
ok(!overload::Overloaded('overload'));

ok(! defined overload::Method($aI, '<<'));
ok(! defined overload::Method($a, '<'));

like (overload::StrVal($aI), qr/^OscalarI=SCALAR\(0x[\da-fA-F]+\)$/);
is(overload::StrVal(\$aI), "@{[\$aI]}");

# Check overloading by methods (specified deep in the ISA tree).
{
  package OscalarII;
  @ISA = 'OscalarI';
  sub Oscalar::lshft {"_<<_" . shift() . "_<<_"}
  eval "package OscalarI; use overload '<<' => 'lshft', '|' => 'lshft'";
}

$aaII = "087";
$aII = \$aaII;
bless $aII, 'OscalarII';
bless \$fake, 'OscalarI';		# update the hash
is(($aI | 3), '_<<_xx_<<_');
# warn $aII << 3;
is(($aII << 3), '_<<_087_<<_');

{
  BEGIN { $int = 7; overload::constant 'integer' => sub {$int++; shift}; }
  $out = 2**10;
}
is($int, 9);
is($out, 1024);
is($int, 9);
{
  BEGIN { overload::constant 'integer' => sub {$int++; shift()+1}; }
  eval q{$out = 42};
}
is($int, 10);
is($out, 43);

$foo = 'foo';
$foo1 = 'f\'o\\o';
{
  BEGIN { $q = $qr = 7; 
	  overload::constant 'q' => sub {$q++; push @q, shift, ($_[1] || 'none'); shift},
			     'qr' => sub {$qr++; push @qr, shift, ($_[1] || 'none'); shift}; }
  $out = 'foo';
  $out1 = 'f\'o\\o';
  $out2 = "a\a$foo,\,";
  /b\b$foo.\./;
}

is($out, 'foo');
is($out, $foo);
is($out1, 'f\'o\\o');
is($out1, $foo1);
is($out2, "a\afoo,\,");
is("@q", "foo q f'o\\\\o q a\\a qq ,\\, qq");
is($q, 11);
is("@qr", "b\\b qq .\\. qq");
is($qr, 9);

{
  $_ = '!<b>!foo!<-.>!';
  BEGIN { overload::constant 'q' => sub {push @q1, shift, ($_[1] || 'none'); "_<" . (shift) . ">_"},
			     'qr' => sub {push @qr1, shift, ($_[1] || 'none'); "!<" . (shift) . ">!"}; }
  $out = 'foo';
  $out1 = 'f\'o\\o';
  $out2 = "a\a$foo,\,";
  $res = /b\b$foo.\./;
  $a = <<EOF;
oups
EOF
  $b = <<'EOF';
oups1
EOF
  $c = bareword;
  m'try it';
  s'first part'second part';
  s/yet another/tail here/;
  tr/A-Z/a-z/;
}

is($out, '_<foo>_');
is($out1, '_<f\'o\\o>_');
is($out2, "_<a\a>_foo_<,\,>_");
is("@q1", "foo q f'o\\\\o q a\\a qq ,\\, qq oups
 qq oups1
 q second part q tail here s A-Z tr a-z tr");
is("@qr1", "b\\b qq .\\. qq try it q first part q yet another qq");
is($res, 1);
is($a, "_<oups
>_");
is($b, "_<oups1
>_");
is($c, "bareword");

{
  package symbolic;		# Primitive symbolic calculator
  use overload nomethod => \&wrap, '""' => \&str, '0+' => \&num,
      '=' => \&cpy, '++' => \&inc, '--' => \&dec;

  sub new { shift; bless ['n', @_] }
  sub cpy {
    my $self = shift;
    bless [@$self], ref $self;
  }
  sub inc { $_[0] = bless ['++', $_[0], 1]; }
  sub dec { $_[0] = bless ['--', $_[0], 1]; }
  sub wrap {
    my ($obj, $other, $inv, $meth) = @_;
    if ($meth eq '++' or $meth eq '--') {
      @$obj = ($meth, (bless [@$obj]), 1); # Avoid circular reference
      return $obj;
    }
    ($obj, $other) = ($other, $obj) if $inv;
    bless [$meth, $obj, $other];
  }
  sub str {
    my ($meth, $a, $b) = @{+shift};
    $a = 'u' unless defined $a;
    if (defined $b) {
      "[$meth $a $b]";
    } else {
      "[$meth $a]";
    }
  } 
  my %subr = ( 'n' => sub {$_[0]} );
  foreach my $op (split " ", $overload::ops{with_assign}) {
    $subr{$op} = $subr{"$op="} = eval "sub {shift() $op shift()}";
  }
  my @bins = qw(binary 3way_comparison num_comparison str_comparison);
  foreach my $op (split " ", "@overload::ops{ @bins }") {
    $subr{$op} = eval "sub {shift() $op shift()}";
  }
  foreach my $op (split " ", "@overload::ops{qw(unary func)}") {
    $subr{$op} = eval "sub {$op shift()}";
  }
  $subr{'++'} = $subr{'+'};
  $subr{'--'} = $subr{'-'};
  
  sub num {
    my ($meth, $a, $b) = @{+shift};
    my $subr = $subr{$meth} 
      or die "Do not know how to ($meth) in symbolic";
    $a = $a->num if ref $a eq __PACKAGE__;
    $b = $b->num if ref $b eq __PACKAGE__;
    $subr->($a,$b);
  }
  sub TIESCALAR { my $pack = shift; $pack->new(@_) }
  sub FETCH { shift }
  sub nop {  }		# Around a bug
  sub vars { my $p = shift; tie($_, $p), $_->nop foreach @_; }
  sub STORE { 
    my $obj = shift; 
    $#$obj = 1; 
    $obj->[1] = shift;
  }
}

{
  my $foo = new symbolic 11;
  my $baz = $foo++;
  is((sprintf "%d", $foo), '12');
  is((sprintf "%d", $baz), '11');
  my $bar = $foo;
  $baz = ++$foo;
  is((sprintf "%d", $foo), '13');
  is((sprintf "%d", $bar), '12');
  is((sprintf "%d", $baz), '13');
  my $ban = $foo;
  $baz = ($foo += 1);
  is((sprintf "%d", $foo), '14');
  is((sprintf "%d", $bar), '12');
  is((sprintf "%d", $baz), '14');
  is((sprintf "%d", $ban), '13');
  $baz = 0;
  $baz = $foo++;
  is((sprintf "%d", $foo), '15');
  is((sprintf "%d", $baz), '14');
  is("$foo", '[++ [+= [++ [++ [n 11] 1] 1] 1] 1]');
}

{
  my $iter = new symbolic 2;
  my $side = new symbolic 1;
  my $cnt = $iter;
  
  while ($cnt) {
    $cnt = $cnt - 1;		# The "simple" way
    $side = (sqrt(1 + $side**2) - 1)/$side;
  }
  my $pi = $side*(2**($iter+2));
  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
  is((sprintf "%f", $pi), '3.182598');
}

{
  my $iter = new symbolic 2;
  my $side = new symbolic 1;
  my $cnt = $iter;
  
  while ($cnt--) {
    $side = (sqrt(1 + $side**2) - 1)/$side;
  }
  my $pi = $side*(2**($iter+2));
  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
  is((sprintf "%f", $pi), '3.182598');
}

{
  my ($a, $b);
  symbolic->vars($a, $b);
  my $c = sqrt($a**2 + $b**2);
  $a = 3; $b = 4;
  is((sprintf "%d", $c), '5');
  $a = 12; $b = 5;
  is((sprintf "%d", $c), '13');
}

{
  package symbolic1;		# Primitive symbolic calculator
  # Mutator inc/dec
  use overload nomethod => \&wrap, '""' => \&str, '0+' => \&num, '=' => \&cpy;

  sub new { shift; bless ['n', @_] }
  sub cpy {
    my $self = shift;
    bless [@$self], ref $self;
  }
  sub wrap {
    my ($obj, $other, $inv, $meth) = @_;
    if ($meth eq '++' or $meth eq '--') {
      @$obj = ($meth, (bless [@$obj]), 1); # Avoid circular reference
      return $obj;
    }
    ($obj, $other) = ($other, $obj) if $inv;
    bless [$meth, $obj, $other];
  }
  sub str {
    my ($meth, $a, $b) = @{+shift};
    $a = 'u' unless defined $a;
    if (defined $b) {
      "[$meth $a $b]";
    } else {
      "[$meth $a]";
    }
  } 
  my %subr = ( 'n' => sub {$_[0]} );
  foreach my $op (split " ", $overload::ops{with_assign}) {
    $subr{$op} = $subr{"$op="} = eval "sub {shift() $op shift()}";
  }
  my @bins = qw(binary 3way_comparison num_comparison str_comparison);
  foreach my $op (split " ", "@overload::ops{ @bins }") {
    $subr{$op} = eval "sub {shift() $op shift()}";
  }
  foreach my $op (split " ", "@overload::ops{qw(unary func)}") {
    $subr{$op} = eval "sub {$op shift()}";
  }
  $subr{'++'} = $subr{'+'};
  $subr{'--'} = $subr{'-'};
  
  sub num {
    my ($meth, $a, $b) = @{+shift};
    my $subr = $subr{$meth} 
      or die "Do not know how to ($meth) in symbolic";
    $a = $a->num if ref $a eq __PACKAGE__;
    $b = $b->num if ref $b eq __PACKAGE__;
    $subr->($a,$b);
  }
  sub TIESCALAR { my $pack = shift; $pack->new(@_) }
  sub FETCH { shift }
  sub nop {  }		# Around a bug
  sub vars { my $p = shift; tie($_, $p), $_->nop foreach @_; }
  sub STORE { 
    my $obj = shift; 
    $#$obj = 1; 
    $obj->[1] = shift;
  }
}

{
  my $foo = new symbolic1 11;
  my $baz = $foo++;
  is((sprintf "%d", $foo), '12');
  is((sprintf "%d", $baz), '11');
  my $bar = $foo;
  $baz = ++$foo;
  is((sprintf "%d", $foo), '13');
  is((sprintf "%d", $bar), '12');
  is((sprintf "%d", $baz), '13');
  my $ban = $foo;
  $baz = ($foo += 1);
  is((sprintf "%d", $foo), '14');
  is((sprintf "%d", $bar), '12');
  is((sprintf "%d", $baz), '14');
  is((sprintf "%d", $ban), '13');
  $baz = 0;
  $baz = $foo++;
  is((sprintf "%d", $foo), '15');
  is((sprintf "%d", $baz), '14');
  is("$foo", '[++ [+= [++ [++ [n 11] 1] 1] 1] 1]');
}

{
  my $iter = new symbolic1 2;
  my $side = new symbolic1 1;
  my $cnt = $iter;
  
  while ($cnt) {
    $cnt = $cnt - 1;		# The "simple" way
    $side = (sqrt(1 + $side**2) - 1)/$side;
  }
  my $pi = $side*(2**($iter+2));
  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
  is((sprintf "%f", $pi), '3.182598');
}

{
  my $iter = new symbolic1 2;
  my $side = new symbolic1 1;
  my $cnt = $iter;
  
  while ($cnt--) {
    $side = (sqrt(1 + $side**2) - 1)/$side;
  }
  my $pi = $side*(2**($iter+2));
  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
  is((sprintf "%f", $pi), '3.182598');
}

{
  my ($a, $b);
  symbolic1->vars($a, $b);
  my $c = sqrt($a**2 + $b**2);
  $a = 3; $b = 4;
  is((sprintf "%d", $c), '5');
  $a = 12; $b = 5;
  is((sprintf "%d", $c), '13');
}

{
  package two_face;		# Scalars with separate string and
                                # numeric values.
  sub new { my $p = shift; bless [@_], $p }
  use overload '""' => \&str, '0+' => \&num, fallback => 1;
  sub num {shift->[1]}
  sub str {shift->[0]}
}

{
  my $seven = new two_face ("vii", 7);
  is((sprintf "seven=$seven, seven=%d, eight=%d", $seven, $seven+1),
	'seven=vii, seven=7, eight=8');
  is(scalar ($seven =~ /i/), '1');
}

{
  package sorting;
  use overload 'cmp' => \&comp;
  sub new { my ($p, $v) = @_; bless \$v, $p }
  sub comp { my ($x,$y) = @_; ($$x * 3 % 10) <=> ($$y * 3 % 10) or $$x cmp $$y }
}
{
  my @arr = map sorting->new($_), 0..12;
  my @sorted1 = sort @arr;
  my @sorted2 = map $$_, @sorted1;
  is("@sorted2", '0 10 7 4 1 11 8 5 12 2 9 6 3');
}
{
  package iterator;
  use overload '<>' => \&iter;
  sub new { my ($p, $v) = @_; bless \$v, $p }
  sub iter { my ($x) = @_; return undef if $$x < 0; return $$x--; }
}

# XXX iterator overload not intended to work with CORE::GLOBAL?
if (defined &CORE::GLOBAL::glob) {
  is('1', '1');
  is('1', '1');
  is('1', '1');
}
else {
  my $iter = iterator->new(5);
  my $acc = '';
  my $out;
  $acc .= " $out" while $out = <${iter}>;
  is($acc, ' 5 4 3 2 1 0');
  $iter = iterator->new(5);
  is(scalar <${iter}>, '5');
  $acc = '';
  $acc .= " $out" while $out = <$iter>;
  is($acc, ' 4 3 2 1 0');
}
{
  package deref;
  use overload '%{}' => \&hderef, '&{}' => \&cderef, 
    '*{}' => \&gderef, '${}' => \&sderef, '@{}' => \&aderef;
  sub new { my ($p, $v) = @_; bless \$v, $p }
  sub deref {
    my ($self, $key) = (shift, shift);
    my $class = ref $self;
    bless $self, 'deref::dummy'; # Disable overloading of %{} 
    my $out = $self->{$key};
    bless $self, $class;	# Restore overloading
    $out;
  }
  sub hderef {shift->deref('h')}
  sub aderef {shift->deref('a')}
  sub cderef {shift->deref('c')}
  sub gderef {shift->deref('g')}
  sub sderef {shift->deref('s')}
}
{
  my $deref = bless { h => { foo => 5 , fake => 23 },
		      c => sub {return shift() + 34},
		      's' => \123,
		      a => [11..13],
		      g => \*srt,
		    }, 'deref';
  # Hash:
  my @cont = sort %$deref;
  if ("\t" eq "\011") { # ASCII
      is("@cont", '23 5 fake foo');
  } 
  else {                # EBCDIC alpha-numeric sort order
      is("@cont", 'fake foo 23 5');
  }
  my @keys = sort keys %$deref;
  is("@keys", 'fake foo');
  my @val = sort values %$deref;
  is("@val", '23 5');
  is($deref->{foo}, 5);
  is(defined $deref->{bar}, '');
  my $key;
  @keys = ();
  push @keys, $key while $key = each %$deref;
  @keys = sort @keys;
  is("@keys", 'fake foo');
  is(exists $deref->{bar}, '');
  is(exists $deref->{foo}, 1);
  # Code:
  is($deref->(5), 39);
  is(&$deref(6), 40);
  sub xxx_goto { goto &$deref }
  is(xxx_goto(7), 41);
  my $srt = bless { c => sub {$b <=> $a}
		  }, 'deref';
  *srt = \&$srt;
  my @sorted = sort srt 11, 2, 5, 1, 22;
  is("@sorted", '22 11 5 2 1');
  # Scalar
  is($$deref, 123);
  # Code
  @sorted = sort $srt 11, 2, 5, 1, 22;
  is("@sorted", '22 11 5 2 1');
  # Array
  is("@$deref", '11 12 13');
  is($#$deref, '2');
  my $l = @$deref;
  is($l, 3);
  is($deref->[2], '13');
  $l = pop @$deref;
  is($l, 13);
  $l = 1;
  is($deref->[$l], '12');
  # Repeated dereference
  my $double = bless { h => $deref,
		     }, 'deref';
  is($double->{foo}, 5);
}

{
  package two_refs;
  use overload '%{}' => \&gethash, '@{}' => sub { ${shift()} };
  sub new { 
    my $p = shift; 
    bless \ [@_], $p;
  }
  sub gethash {
    my %h;
    my $self = shift;
    tie %h, ref $self, $self;
    \%h;
  }

  sub TIEHASH { my $p = shift; bless \ shift, $p }
  my %fields;
  my $i = 0;
  $fields{$_} = $i++ foreach qw{zero one two three};
  sub STORE { 
    my $self = ${shift()};
    my $key = $fields{shift()};
    defined $key or die "Out of band access";
    $$self->[$key] = shift;
  }
  sub FETCH { 
    my $self = ${shift()};
    my $key = $fields{shift()};
    defined $key or die "Out of band access";
    $$self->[$key];
  }
}

my $bar = new two_refs 3,4,5,6;
$bar->[2] = 11;
is($bar->{two}, 11);
$bar->{three} = 13;
is($bar->[3], 13);

{
  package two_refs_o;
  @ISA = ('two_refs');
}

$bar = new two_refs_o 3,4,5,6;
$bar->[2] = 11;
is($bar->{two}, 11);
$bar->{three} = 13;
is($bar->[3], 13);

{
  package two_refs1;
  use overload '%{}' => sub { ${shift()}->[1] },
               '@{}' => sub { ${shift()}->[0] };
  sub new { 
    my $p = shift; 
    my $a = [@_];
    my %h;
    tie %h, $p, $a;
    bless \ [$a, \%h], $p;
  }
  sub gethash {
    my %h;
    my $self = shift;
    tie %h, ref $self, $self;
    \%h;
  }

  sub TIEHASH { my $p = shift; bless \ shift, $p }
  my %fields;
  my $i = 0;
  $fields{$_} = $i++ foreach qw{zero one two three};
  sub STORE { 
    my $a = ${shift()};
    my $key = $fields{shift()};
    defined $key or die "Out of band access";
    $a->[$key] = shift;
  }
  sub FETCH { 
    my $a = ${shift()};
    my $key = $fields{shift()};
    defined $key or die "Out of band access";
    $a->[$key];
  }
}

$bar = new two_refs_o 3,4,5,6;
$bar->[2] = 11;
is($bar->{two}, 11);
$bar->{three} = 13;
is($bar->[3], 13);

{
  package two_refs1_o;
  @ISA = ('two_refs1');
}

$bar = new two_refs1_o 3,4,5,6;
$bar->[2] = 11;
is($bar->{two}, 11);
$bar->{three} = 13;
is($bar->[3], 13);

{
  package B;
  use overload bool => sub { ${+shift} };
}

my $aaa;
{ my $bbbb = 0; $aaa = bless \$bbbb, B }

is !$aaa, 1;

unless ($aaa) {
  pass();
} else {
  fail();
}

# check that overload isn't done twice by join
{ my $c = 0;
  package Join;
  use overload '""' => sub { $c++ };
  my $x = join '', bless([]), 'pq', bless([]);
  main::is $x, '0pq1';
};

# Test module-specific warning
{
    # check the Odd number of arguments for overload::constant warning
    my $a = "" ;
    local $SIG{__WARN__} = sub {$a = $_[0]} ;
    $x = eval ' overload::constant "integer" ; ' ;
    is($a, "");
    use warnings 'overload' ;
    $x = eval ' overload::constant "integer" ; ' ;
    like($a, qr/^Odd number of arguments for overload::constant at/);
}

{
    # check the `$_[0]' is not an overloadable type warning
    my $a = "" ;
    local $SIG{__WARN__} = sub {$a = $_[0]} ;
    $x = eval ' overload::constant "fred" => sub {} ; ' ;
    is($a, "");
    use warnings 'overload' ;
    $x = eval ' overload::constant "fred" => sub {} ; ' ;
    like($a, qr/^`fred' is not an overloadable type at/);
}

{
    # check the `$_[1]' is not a code reference warning
    my $a = "" ;
    local $SIG{__WARN__} = sub {$a = $_[0]} ;
    $x = eval ' overload::constant "integer" => 1; ' ;
    is($a, "");
    use warnings 'overload' ;
    $x = eval ' overload::constant "integer" => 1; ' ;
    like($a, qr/^`1' is not a code reference at/);
}

{
  my $c = 0;
  package ov_int1;
  use overload '""'    => sub { 3+shift->[0] },
               '0+'    => sub { 10+shift->[0] },
               'int'   => sub { 100+shift->[0] };
  sub new {my $p = shift; bless [shift], $p}

  package ov_int2;
  use overload '""'    => sub { 5+shift->[0] },
               '0+'    => sub { 30+shift->[0] },
               'int'   => sub { 'ov_int1'->new(1000+shift->[0]) };
  sub new {my $p = shift; bless [shift], $p}

  package noov_int;
  use overload '""'    => sub { 2+shift->[0] },
               '0+'    => sub { 9+shift->[0] };
  sub new {my $p = shift; bless [shift], $p}

  package main;

  my $x = new noov_int 11;
  my $int_x = int $x;
  main::is("$int_x", 20);
  $x = new ov_int1 31;
  $int_x = int $x;
  main::is("$int_x", 131);
  $x = new ov_int2 51;
  $int_x = int $x;
  main::is("$int_x", 1054);
}

# make sure that we don't infinitely recurse
{
  my $c = 0;
  package Recurse;
  use overload '""'    => sub { shift },
               '0+'    => sub { shift },
               'bool'  => sub { shift },
               fallback => 1;
  my $x = bless([]);
  # For some reason beyond me these have to be oks rather than likes.
  main::ok("$x" =~ /Recurse=ARRAY/);
  main::ok($x);
  main::ok($x+0 =~ qr/Recurse=ARRAY/);
}

# BugID 20010422.003
package Foo;

use overload
  'bool' => sub { return !$_[0]->is_zero() || undef; }
;
 
sub is_zero
  {
  my $self = shift;
  return $self->{var} == 0;
  }

sub new
  {
  my $class = shift;
  my $self =  {};
  $self->{var} = shift;
  bless $self,$class;
  }

package main;

use strict;

my $r = Foo->new(8);
$r = Foo->new(0);

is(($r || 0), 0);

package utf8_o;

use overload 
  '""'  =>  sub { return $_[0]->{var}; }
  ;
  
sub new
  {
    my $class = shift;
    my $self =  {};
    $self->{var} = shift;
    bless $self,$class;
  }

package main;


my $utfvar = new utf8_o 200.2.1;
is("$utfvar", 200.2.1); # 223 - stringify
is("a$utfvar", "a".200.2.1); # 224 - overload via sv_2pv_flags

# 225..227 -- more %{} tests.  Hangs in 5.6.0, okay in later releases.
# Basically this example implements strong encapsulation: if Hderef::import()
# were to eval the overload code in the caller's namespace, the privatisation
# would be quite transparent.
package Hderef;
use overload '%{}' => sub { (caller(0))[0] eq 'Foo' ? $_[0] : die "zap" };
package Foo;
@Foo::ISA = 'Hderef';
sub new { bless {}, shift }
sub xet { @_ == 2 ? $_[0]->{$_[1]} :
	  @_ == 3 ? ($_[0]->{$_[1]} = $_[2]) : undef }
package main;
my $a = Foo->new;
$a->xet('b', 42);
is ($a->xet('b'), 42);
ok (!defined eval { $a->{b} });
like ($@, qr/zap/);

{
   package t229;
   use overload '='  => sub { 42 },
                '++' => sub { my $x = ${$_[0]}; $_[0] };
   sub new { my $x = 42; bless \$x }

   my $warn;
   {  
     local $SIG{__WARN__} = sub { $warn++ };
      my $x = t229->new;
      my $y = $x;
      eval { $y++ };
   }
   main::ok (!$warn);
}

{
    my ($int, $out1, $out2);
    {
        BEGIN { $int = 0; overload::constant 'integer' => sub {$int++; 17}; }
        $out1 = 0;
        $out2 = 1;
    }
    is($int,  2,  "#24313");	# 230
    is($out1, 17, "#24313");	# 231
    is($out2, 17, "#24313");	# 232
}

{
    package Numify;
    use overload (qw(0+ numify fallback 1));

    sub new {
	my $val = $_[1];
	bless \$val, $_[0];
    }

    sub numify { ${$_[0]} }
}

{
    package perl31793;
    use overload cmp => sub { 0 };
    package perl31793_fb;
    use overload cmp => sub { 0 }, fallback => 1;
    package main;
    my $o  = bless [], 'perl31793';
    my $of = bless [], 'perl31793_fb';
    my $no = bless [], 'no_overload';
    like(overload::StrVal(\"scalar"), qr/^SCALAR\(0x[0-9a-f]+\)$/);
    like(overload::StrVal([]),        qr/^ARRAY\(0x[0-9a-f]+\)$/);
    like(overload::StrVal({}),        qr/^HASH\(0x[0-9a-f]+\)$/);
    like(overload::StrVal(sub{1}),    qr/^CODE\(0x[0-9a-f]+\)$/);
    like(overload::StrVal(\*GLOB),    qr/^GLOB\(0x[0-9a-f]+\)$/);
    like(overload::StrVal(\$o),       qr/^REF\(0x[0-9a-f]+\)$/);
    like(overload::StrVal(qr/a/),     qr/^Regexp=REGEXP\(0x[0-9a-f]+\)$/);
    like(overload::StrVal($o),        qr/^perl31793=ARRAY\(0x[0-9a-f]+\)$/);
    like(overload::StrVal($of),       qr/^perl31793_fb=ARRAY\(0x[0-9a-f]+\)$/);
    like(overload::StrVal($no),       qr/^no_overload=ARRAY\(0x[0-9a-f]+\)$/);
}

# These are all check that overloaded values rather than reference addresses
# are what is getting tested.
my ($two, $one, $un, $deux) = map {new Numify $_} 2, 1, 1, 2;
my ($ein, $zwei) = (1, 2);

my %map = (one => 1, un => 1, ein => 1, deux => 2, two => 2, zwei => 2);
foreach my $op (qw(<=> == != < <= > >=)) {
    foreach my $l (keys %map) {
	foreach my $r (keys %map) {
	    my $ocode = "\$$l $op \$$r";
	    my $rcode = "$map{$l} $op $map{$r}";

	    my $got = eval $ocode;
	    die if $@;
	    my $expect = eval $rcode;
	    die if $@;
	    is ($got, $expect, $ocode) or print "# $rcode\n";
	}
    }
}
{
    # check that overloading works in regexes
    {
	package Foo493;
	use overload
	    '""' => sub { "^$_[0][0]\$" },
	    '.'  => sub { 
		    bless [
			     $_[2]
			    ? (ref $_[1] ? $_[1][0] : $_[1]) . ':' .$_[0][0] 
			    : $_[0][0] . ':' . (ref $_[1] ? $_[1][0] : $_[1])
		    ], 'Foo493'
			};
    }

    my $a = bless [ "a" ], 'Foo493';
    like('a', qr/$a/);
    like('x:a', qr/x$a/);
    like('x:a:=', qr/x$a=$/);
    like('x:a:a:=', qr/x$a$a=$/);

}

{
    {
        package QRonly;
        use overload qr => sub { qr/x/ }, fallback => 1;
    }
    {
        my $x = bless [], "QRonly";

        # like tries to be too clever, and decides that $x-stringified
        # doesn't look like a regex
        ok("x" =~ $x, "qr-only matches");
        ok("y" !~ $x, "qr-only doesn't match what it shouldn't");
        ok("xx" =~ /x$x/, "qr-only matches with concat");
        like("$x", qr/^QRonly=ARRAY/, "qr-only doesn't have string overload");

        my $qr = bless qr/y/, "QRonly";
        ok("x" =~ $qr, "qr with qr-overload uses overload");
        ok("y" !~ $qr, "qr with qr-overload uses overload");
        is("$qr", "".qr/y/, "qr with qr-overload stringify");

        my $rx = $$qr;
        ok("y" =~ $rx, "bare rx with qr-overload doesn't overload match");
        ok("x" !~ $rx, "bare rx with qr-overload doesn't overload match");
        is("$rx", "".qr/y/, "bare rx with qr-overload stringify");
    }
    {
        package QRandSTR;
        use overload qr => sub { qr/x/ }, q/""/ => sub { "y" };
    }
    {
        my $x = bless [], "QRandSTR";
        ok("x" =~ $x, "qr+str uses qr for match");
        ok("y" !~ $x, "qr+str uses qr for match");
        ok("xx" =~ /x$x/, "qr+str uses qr for match with concat");
        is("$x", "y", "qr+str uses str for stringify");

        my $qr = bless qr/z/, "QRandSTR";
        is("$qr", "y", "qr with qr+str uses str for stringify");
        ok("xx" =~ /x$x/, "qr with qr+str uses qr for match");

        my $rx = $$qr;
        ok("z" =~ $rx, "bare rx with qr+str doesn't overload match");
        is("$rx", "".qr/z/, "bare rx with qr+str doesn't overload stringify");
    }
    {
        package QRany;
        use overload qr => sub { $_[0]->(@_) };

        package QRself;
        use overload qr => sub { $_[0] };
    }
    {
        my $rx = bless sub { ${ qr/x/ } }, "QRany";
        ok("x" =~ $rx, "qr overload accepts a bare rx");
        ok("y" !~ $rx, "qr overload accepts a bare rx");

        my $str = bless sub { "x" }, "QRany";
        ok(!eval { "x" =~ $str }, "qr overload doesn't accept a string");
        like($@, qr/^Overloaded qr did not return a REGEXP/, "correct error");

        my $oqr = bless qr/z/, "QRandSTR";
        my $oqro = bless sub { $oqr }, "QRany";
        ok("z" =~ $oqro, "qr overload doesn't recurse");

        my $qrs = bless qr/z/, "QRself";
        ok("z" =~ $qrs, "qr overload can return self");
    }
    {
        package STRonly;
        use overload q/""/ => sub { "x" };

        package STRonlyFB;
        use overload q/""/ => sub { "x" }, fallback => 1;
    }
    {
        my $fb = bless [], "STRonlyFB";
        ok("x" =~ $fb, "qr falls back to \"\"");
        ok("y" !~ $fb, "qr falls back to \"\"");

        my $nofb = bless [], "STRonly";
        ok("x" =~ $nofb, "qr falls back even without fallback");
        ok("y" !~ $nofb, "qr falls back even without fallback");
    }
}

{
    my $twenty_three = 23;
    # Check that constant overloading propagates into evals
    BEGIN { overload::constant integer => sub { 23 } }
    is(eval "17", $twenty_three);
}

{
    package Sklorsh;
    use overload
	bool     => sub { shift->is_cool };

    sub is_cool {
	$_[0]->{name} eq 'cool';
    }

    sub delete {
	undef %{$_[0]};
	bless $_[0], 'Brap';
	return 1;
    }

    sub delete_with_self {
	my $self = shift;
	undef %$self;
	bless $self, 'Brap';
	return 1;
    }

    package Brap;

    1;

    package main;

    my $obj;
    $obj = bless {name => 'cool'}, 'Sklorsh';
    $obj->delete;
    ok(eval {if ($obj) {1}; 1}, $@ || 'reblessed into nonexistent namespace');

    $obj = bless {name => 'cool'}, 'Sklorsh';
    $obj->delete_with_self;
    ok (eval {if ($obj) {1}; 1}, $@);
    
    my $a = $b = {name => 'hot'};
    bless $b, 'Sklorsh';
    is(ref $a, 'Sklorsh');
    is(ref $b, 'Sklorsh');
    ok(!$b, "Expect overloaded boolean");
    ok(!$a, "Expect overloaded boolean");
}

{
    package Flrbbbbb;
    use overload
	bool	 => sub { shift->{truth} eq 'yes' },
	'0+'	 => sub { shift->{truth} eq 'yes' ? '1' : '0' },
	'!'	 => sub { shift->{truth} eq 'no' },
	fallback => 1;

    sub new { my $class = shift; bless { truth => shift }, $class }

    package main;

    my $yes = Flrbbbbb->new('yes');
    my $x;
    $x = 1 if $yes;			is($x, 1);
    $x = 2 unless $yes;			is($x, 1);
    $x = 3 if !$yes;			is($x, 1);
    $x = 4 unless !$yes;		is($x, 4);

    my $no = Flrbbbbb->new('no');
    $x = 0;
    $x = 1 if $no;			is($x, 0);
    $x = 2 unless $no;			is($x, 2);
    $x = 3 if !$no;			is($x, 3);
    $x = 4 unless !$no;			is($x, 3);

    $x = 0;
    $x = 1 if !$no && $yes;		is($x, 1);
    $x = 2 unless !$no && $yes;		is($x, 1);
    $x = 3 if $no || !$yes;		is($x, 1);
    $x = 4 unless $no || !$yes;		is($x, 4);

    $x = 0;
    $x = 1 if !$no || !$yes;		is($x, 1);
    $x = 2 unless !$no || !$yes;	is($x, 1);
    $x = 3 if !$no && !$yes;		is($x, 1);
    $x = 4 unless !$no && !$yes;	is($x, 4);
}

TODO: {
    local $TODO = 'Test-Simple handling of overloads changed with 0.95_01';

    use Scalar::Util 'weaken';

    package Shklitza;
    use overload '""' => sub {"CLiK KLAK"};

    package Ksshfwoom;

    package main;

    my ($obj, $ref);
    $obj = bless do {my $a; \$a}, 'Shklitza';
    $ref = $obj;

    is ($obj, "CLiK KLAK");
    is ($ref, "CLiK KLAK");

    weaken $ref;
    is ($ref, "CLiK KLAK");

    bless $obj, 'Ksshfwoom';

    like ($obj, qr/^Ksshfwoom=/);
    like ($ref, qr/^Ksshfwoom=/);

    undef $obj;
    is ($ref, undef);
}

{
    package bit;
    # bit operations have overloadable assignment variants too

    sub new { bless \$_[1], $_[0] }

    use overload
          "&=" => sub { bit->new($_[0]->val . ' & ' . $_[1]->val) }, 
          "^=" => sub { bit->new($_[0]->val . ' ^ ' . $_[1]->val) },
          "|"  => sub { bit->new($_[0]->val . ' | ' . $_[1]->val) }, # |= by fallback
          ;

    sub val { ${$_[0]} }

    package main;

    my $a = bit->new(my $va = 'a');
    my $b = bit->new(my $vb = 'b');

    $a &= $b;
    is($a->val, 'a & b', "overloaded &= works");

    my $c = bit->new(my $vc = 'c');

    $b ^= $c;
    is($b->val, 'b ^ c', "overloaded ^= works");

    my $d = bit->new(my $vd = 'd');

    $c |= $d;
    is($c->val, 'c | d', "overloaded |= (by fallback) works");
}

{
    # comparison operators with nomethod (bug 41546)
    my $warning = "";
    my $method;

    package nomethod_false;
    use overload nomethod => sub { $method = 'nomethod'; 0 };

    package nomethod_true;
    use overload nomethod => sub { $method= 'nomethod'; 'true' };

    package main;
    local $^W = 1;
    local $SIG{__WARN__} = sub { $warning = $_[0] };

    my $f = bless [], 'nomethod_false';
    ($warning, $method) = ("", "");
    is($f eq 'whatever', 0, 'nomethod makes eq return 0');
    is($method, 'nomethod');

    my $t = bless [], 'nomethod_true';
    ($warning, $method) = ("", "");
    is($t eq 'whatever', 'true', 'nomethod makes eq return "true"');
    is($method, 'nomethod');
    is($warning, "", 'nomethod eq need not return number');

    eval q{ 
        package nomethod_false;
        use overload cmp => sub { $method = 'cmp'; 0 };
    };
    $f = bless [], 'nomethod_false';
    ($warning, $method) = ("", "");
    ok($f eq 'whatever', 'eq falls back to cmp (nomethod not called)');
    is($method, 'cmp');

    eval q{
        package nomethod_true;
        use overload cmp => sub { $method = 'cmp'; 'true' };
    };
    $t = bless [], 'nomethod_true';
    ($warning, $method) = ("", "");
    ok($t eq 'whatever', 'eq falls back to cmp (nomethod not called)');
    is($method, 'cmp');
    like($warning, qr/isn't numeric/, 'cmp should return number');

}

{
    # nomethod called for '!' after attempted fallback
    my $nomethod_called = 0;

    package nomethod_not;
    use overload nomethod => sub { $nomethod_called = 'yes'; };

    package main;
    my $o = bless [], 'nomethod_not';
    my $res = ! $o;

    is($nomethod_called, 'yes', "nomethod() is called for '!'");
    is($res, 'yes', "nomethod(..., '!') return value propagates");
}

{
    # Subtle bug pre 5.10, as a side effect of the overloading flag being
    # stored on the reference rather than the referent. Despite the fact that
    # objects can only be accessed via references (even internally), the
    # referent actually knows that it's blessed, not the references. So taking
    # a new, unrelated, reference to it gives an object. However, the
    # overloading-or-not flag was on the reference prior to 5.10, and taking
    # a new reference didn't (use to) copy it.

    package kayo;

    use overload '""' => sub {${$_[0]}};

    sub Pie {
	return "$_[0], $_[1]";
    }

    package main;

    my $class = 'kayo';
    my $string = 'bam';
    my $crunch_eth = bless \$string, $class;

    is("$crunch_eth", $string);
    is ($crunch_eth->Pie("Meat"), "$string, Meat");

    my $wham_eth = \$string;

    is("$wham_eth", $string,
       'This reference did not have overloading in 5.8.8 and earlier');
    is ($crunch_eth->Pie("Apple"), "$string, Apple");

    my $class = ref $wham_eth;
    $class =~ s/=.*//;

    # Bless it back into its own class!
    bless $wham_eth, $class;

    is("$wham_eth", $string);
    is ($crunch_eth->Pie("Blackbird"), "$string, Blackbird");
}

{
    package numify_int;
    use overload "0+" => sub { $_[0][0] += 1; 42 };
    package numify_self;
    use overload "0+" => sub { $_[0][0]++; $_[0] };
    package numify_other;
    use overload "0+" => sub { $_[0][0]++; $_[0][1] = bless [], 'numify_int' };
    package numify_by_fallback;
    use overload fallback => 1;

    package main;
    my $o = bless [], 'numify_int';
    is(int($o), 42, 'numifies to integer');
    is($o->[0], 1, 'int() numifies only once');

    my $aref = [];
    my $num_val = int($aref);
    my $r = bless $aref, 'numify_self';
    is(int($r), $num_val, 'numifies to self');
    is($r->[0], 1, 'int() numifies once when returning self');

    my $s = bless [], 'numify_other';
    is(int($s), 42, 'numifies to numification of other object');
    is($s->[0], 1, 'int() numifies once when returning other object');
    is($s->[1][0], 1, 'returned object numifies too');

    my $m = bless $aref, 'numify_by_fallback';
    is(int($m), $num_val, 'numifies to usual reference value');
    is(abs($m), $num_val, 'numifies to usual reference value');
    is(-$m, -$num_val, 'numifies to usual reference value');
    is(0+$m, $num_val, 'numifies to usual reference value');
    is($m+0, $num_val, 'numifies to usual reference value');
    is($m+$m, 2*$num_val, 'numifies to usual reference value');
    is(0-$m, -$num_val, 'numifies to usual reference value');
    is(1*$m, $num_val, 'numifies to usual reference value');
    is(int($m/1), $num_val, 'numifies to usual reference value');
    is($m%100, $num_val%100, 'numifies to usual reference value');
    is($m**1, $num_val, 'numifies to usual reference value');

    is(abs($aref), $num_val, 'abs() of ref');
    is(-$aref, -$num_val, 'negative of ref');
    is(0+$aref, $num_val, 'ref addition');
    is($aref+0, $num_val, 'ref addition');
    is($aref+$aref, 2*$num_val, 'ref addition');
    is(0-$aref, -$num_val, 'subtraction of ref');
    is(1*$aref, $num_val, 'multiplicaton of ref');
    is(int($aref/1), $num_val, 'division of ref');
    is($aref%100, $num_val%100, 'modulo of ref');
    is($aref**1, $num_val, 'exponentiation of ref');
}

{
    package CopyConstructorFallback;
    use overload
        '++'        => sub { "$_[0]"; $_[0] },
        fallback    => 1;
    sub new { bless {} => shift }

    package main;

    my $o = CopyConstructorFallback->new;
    my $x = $o++; # would segfault
    my $y = ++$o;
    is($x, $o, "copy constructor falls back to assignment (postinc)");
    is($y, $o, "copy constructor falls back to assignment (preinc)");
}

# only scalar 'x' should currently overload

{
    package REPEAT;

    my ($x,$n, $nm);

    use overload
	'x'        => sub { $x++; 1 },
	'0+'       => sub { $n++; 1 },
	'nomethod' => sub { $nm++; 1 },
	'fallback' => 0,
    ;

    my $s = bless {};

    package main;

    my @a;
    my $count = 3;

    ($x,$n,$nm) = (0,0,0);
    @a = ((1,2,$s) x $count);
    is("$x-$n-$nm", "0-0-0", 'repeat 1');

    ($x,$n,$nm) = (0,0,0);
    @a = ((1,$s,3) x $count);
    is("$x-$n-$nm", "0-0-0", 'repeat 2');

    ($x,$n,$nm) = (0,0,0);
    @a = ((1,2,3) x $s);
    is("$x-$n-$nm", "0-1-0", 'repeat 3');
}



# RT #57012: magic items need to have mg_get() called before testing for
# overload. Lack of this means that overloaded values returned by eg a
# tied array didn't call overload methods.
# We test here both a tied array and scalar, since the implementation of
# tied  arrays (and hashes) is such that in rvalue context, mg_get is
# called prior to executing the op, while it isn't for a tied scalar.
# We also check that return values are correctly tainted.
# We try against two overload packages; one has all expected methods, the
# other uses only fallback methods.

{

    # @tests holds a list of test cases. Each elem is an array ref with
    # the following entries:
    #
    #  * the value that the overload method should return
    #
    #  * the expression to be evaled. %s is replaced with the
    #       variable being tested ($ta[0], $ts, or $plain)
    #
    #  * a string listing what functions we expect to be called.
    #       Each method appends its name in parentheses, so "(=)(+)" means
    #       we expect the copy constructor and then the add method to be
    #       called.
    #
    #  * like above, but what should be called for the fallback-only test
    #      (in this case, nomethod() identifies itself as "(NM:*)" where *
    #      is the op).  If this value is undef, fallback tests are skipped.
    #
    #  * An array ref of expected counts of calls to FETCH/STORE.
    #      The first three values are:
    #         1. the expected number of FETCHs for a tied array
    #         2. the expected number of FETCHs for a tied scalar
    #         3. the expected number of STOREs
    #       If there are a further three elements present, then
    #       these represent the expected counts for the fallback
    #       version of the tests. If absent, they are assumed to
    #       be the same as for the full method test
    #
    #  * Under the taint version of the tests,  whether we expect
    #       the result to be tainted (for example comparison ops
    #       like '==' don't return a tainted value, even if their
    #       args are.
    my @tests;

    my %subs;
    my $funcs;
    my $use_int;

    BEGIN {
	# A note on what methods to expect to be called, and
	# how many times FETCH/STORE is called:
	#
	# Mutating ops (+=, ++ etc) trigger a copy ('='), since
	# the code can't distingish between something that's been copied:
	#    $a = foo->new(0); $b = $a; refcnt($$b) == 2
	# and overloaded objects stored in ties which will have extra
	# refcounts due to the tied_obj magic and entries on the tmps
	# stack when returning from FETCH etc. So we always copy.

	# This accounts for a '=', and an extra STORE.
	# We also have a FETCH returning the final value from the eval,
	# plus a FETCH in the overload subs themselves: ($_[0][0])
	# triggers one. However, tied agregates have a mechanism to prevent
	# multiple fetches between STOREs, which means that the tied
	# hash skips doing a FETCH during '='.

	for (qw(+ - * / % ** << >> & | ^)) {
	    my $op = $_;
	    $op = '%%' if $op eq '%';
	    my $e = "%s $op= 3";
	    $subs{"$_="} = $e;
	    # ARRAY  FETCH: initial,        sub+=, eval-return,
	    # SCALAR FETCH: initial, sub=,  sub+=, eval-return,
	    # STORE:        copy, mutator
	    push @tests, [ 18, $e, "(=)($_=)", "(=)(NM:$_=)", [ 3, 4, 2 ], 1 ];

	    $subs{$_} =
		"do { my \$arg = %s; \$_[2] ? (3 $op \$arg) : (\$arg $op 3) }";
	    # ARRAY  FETCH: initial
	    # SCALAR FETCH: initial eval-return,
	    push @tests, [ 18, "%s $op 3", "($_)", "(NM:$_)", [ 1, 2, 0 ], 1 ];
	    push @tests, [ 18, "3 $op %s", "($_)", "(NM:$_)", [ 1, 2, 0 ], 1 ];
	}

	# these use string fallback rather than nomethod
	for (qw(x .)) {
	    my $op = $_;
	    my $e = "%s $op= 3";
	    $subs{"$_="} = $e;
	    # For normal case:
	    #   ARRAY  FETCH: initial,        sub+=, eval-return,
	    #   SCALAR FETCH: initial, sub=,  sub+=, eval-return,
	    #          STORE: copy, mutator
	    # for fallback, we just stringify, so eval-return and copy skipped

	    push @tests, [ 18, $e, "(=)($_=)", '("")',
			    [ 3, 4, 2,     2, 3, 1 ], 1 ];

	    $subs{$_} =
		"do { my \$arg = %s; \$_[2] ? (3 $op \$arg) : (\$arg $op 3) }";
	    # ARRAY  FETCH: initial
	    # SCALAR FETCH: initial eval-return,
	    # with fallback, we just stringify, so eval-return skipped,
	    #    but an extra FETCH happens in sub"", except for 'x',
	    #    which passes a copy of the RV to sub"", avoiding the
	    #    second FETCH

	    push @tests, [ 18, "%s $op 3", "($_)", '("")',
			    [ 1, 2, 0,     1, ($_ eq '.' ? 2 : 1), 0 ], 1 ];
	    next if $_ eq 'x'; # repeat only overloads on LHS
	    push @tests, [ 18, "3 $op %s", "($_)", '("")',
			    [ 1, 2, 0,     1, 2, 0 ], 1 ];
	}

	for (qw(++ --)) {
	    my $pre  = "$_%s";
	    my $post = "%s$_";
	    $subs{$_} = $pre;
	    push @tests,
		# ARRAY  FETCH: initial,        sub+=, eval-return,
		# SCALAR FETCH: initial, sub=,  sub+=, eval-return,
		# STORE:        copy, mutator
		[ 18, $pre, "(=)($_)(\"\")", "(=)(NM:$_)(\"\")", [ 3, 4, 2 ], 1 ],
		# ARRAY  FETCH: initial,        sub+=
		# SCALAR FETCH: initial, sub=,  sub+=
		# STORE:        copy, mutator
		[ 18, $post, "(=)($_)(\"\")", "(=)(NM:$_)(\"\")", [ 2, 3, 2 ], 1 ];
	}

	# For the non-mutator ops, we have a initial FETCH,
	# an extra FETCH within the sub itself for the scalar option,
	# and no STOREs

	for (qw(< <= >  >= == != lt le gt ge eq ne)) {
	    my $e = "%s $_ 3";
	    $subs{$_} = $e;
	    push @tests, [ 3, $e, "($_)", "(NM:$_)", [ 1, 2, 0 ], 0 ];
	}
	for (qw(<=> cmp)) {
	    my $e = "%s $_ 3";
	    $subs{$_} = $e;
	    push @tests, [ 3, $e, "($_)", "(NM:$_)", [ 1, 2, 0 ], 1 ];
	}
	for (qw(atan2)) {
	    my $e = "$_ %s, 3";
	    $subs{$_} = $e;
	    push @tests, [ 18, $e, "($_)", "(NM:$_)", [ 1, 2, 0 ], 1 ];
	}
	for (qw(cos sin exp abs log sqrt int ~)) {
	    my $e = "$_(%s)";
	    $subs{$_} = $e;
	    push @tests, [ 1.23, $e, "($_)",
		    ($_ eq 'int' ? '(0+)' : "(NM:$_)") , [ 1, 2, 0 ], 1 ];
	}
	for (qw(!)) {
	    my $e = "$_(%s)";
	    $subs{$_} = $e;
	    push @tests, [ 1.23, $e, "($_)", '(0+)', [ 1, 2, 0 ], 0 ];
	}
	for (qw(-)) {
	    my $e = "$_(%s)";
	    $subs{neg} = $e;
	    push @tests, [ 18, $e, '(neg)', '(NM:neg)', [ 1, 2, 0 ], 1 ];
	}
	my $e = '(%s) ? 1 : 0';
	$subs{bool} = $e;
	push @tests, [ 18, $e, '(bool)', '(0+)', [ 1, 2, 0 ], 0 ];

	# note: this is testing unary qr, not binary =~
	$subs{qr} = '(qr/%s/)';
	push @tests, [ "abc", '"abc" =~ (%s)', '(qr)', '("")', [ 1, 2, 0 ], 0 ];

	$e = '"abc" ~~ (%s)';
	$subs{'~~'} = $e;
	push @tests, [ "abc", $e, '(~~)', '(NM:~~)', [ 1, 1, 0 ], 0 ];

	$subs{'-X'} = 'do { my $f = (%s);'
		    . '$_[1] eq "r" ? (-r ($f)) :'
		    . '$_[1] eq "e" ? (-e ($f)) :'
		    . '$_[1] eq "f" ? (-f ($f)) :'
		    . '$_[1] eq "l" ? (-l ($f)) :'
		    . '$_[1] eq "t" ? (-t ($f)) :'
		    . '$_[1] eq "T" ? (-T ($f)) : 0;}';
	# Note - we don't care what these filetests return, as
	# long as the tied and untied versions return the same value.
	# The flags below are chosen to test all uses of tryAMAGICftest_MG
	for (qw(r e f l t T)) {
	    push @tests, [ 'TEST', "-$_ (%s)", '(-X)', '("")', [ 1, 2, 0 ], 0 ];
	}

	$subs{'${}'} = '%s';
	push @tests, [ do {my $s=99; \$s}, '${%s}', '(${})', undef, [ 1, 1, 0 ], 0 ];

	# we skip testing '@{}' here because too much of this test
	# framework involves array dereferences!

	$subs{'%{}'} = '%s';
	push @tests, [ {qw(a 1 b 2 c 3)}, 'join "", sort keys %%{%s}',
			'(%{})', undef, [ 1, 2, 0 ], 0 ];

	$subs{'&{}'} = '%s';
	push @tests, [ sub {99}, 'do {&{%s} for 1,2}',
			    '(&{})(&{})', undef, [ 2, 2, 0 ], 0 ];

	our $RT57012A = 88;
	our $RT57012B;
	$subs{'*{}'} = '%s';
	push @tests, [ \*RT57012A, '*RT57012B = *{%s}; our $RT57012B',
		'(*{})', undef, [ 1, 1, 0 ], 0 ];

	# XXX TODO: '<>'

	# eval should do tie, overload on its arg before checking taint */
	push @tests, [ '1;', 'eval q(eval %s); $@ =~ /Insecure/',
		'("")', '("")', [ 1, 2, 0 ], 0 ];


	for my $sub (keys %subs) {
	    my $term = $subs{$sub};
	    my $t = sprintf $term, '$_[0][0]';
	    my $e ="sub { \$funcs .= '($sub)'; my \$r; if (\$use_int) {"
		. "use integer; \$r = ($t) } else { \$r = ($t) } \$r }";
	    $subs{$sub} = eval $e;
	    die "Compiling sub gave error:\n<$e>\n<$@>\n" if $@;
	}
    }

    my $fetches;
    my $stores;

    package RT57012_OV;

    use overload
	%subs,
	"="   => sub { $funcs .= '(=)';  bless [ $_[0][0] ] },
	'0+'  => sub { $funcs .= '(0+)'; 0 + $_[0][0] },
	'""'  => sub { $funcs .= '("")'; "$_[0][0]"   },
	;

    package RT57012_OV_FB; # only contains fallback conversion functions

    use overload
	"="   => sub { $funcs .= '(=)';  bless [ $_[0][0] ] },
	'0+'  => sub { $funcs .= '(0+)'; 0 + $_[0][0] },
	'""'  => sub { $funcs .= '("")'; "$_[0][0]"   },
	"nomethod" => sub {
			$funcs .= "(NM:$_[3])";
			my $e = defined($_[1])
				? $_[3] eq 'atan2'
				    ? $_[2]
				       ? "atan2(\$_[1],\$_[0][0])"
				       : "atan2(\$_[0][0],\$_[1])"
				    : $_[2]
					? "\$_[1] $_[3] \$_[0][0]"
					: "\$_[0][0] $_[3] \$_[1]"
				: $_[3] eq 'neg'
				    ? "-\$_[0][0]"
				    : "$_[3](\$_[0][0])";
			my $r;
			if ($use_int) {
			    use integer; $r = eval $e;
			}
			else {
			    $r = eval $e;
			}
			::diag("eval of nomethod <$e> gave <$@>") if $@;
			$r;
		    }

	;

    package RT57012_TIE_S;

    my $tie_val;
    sub TIESCALAR { bless [ bless [ $tie_val ], $_[1] ] }
    sub FETCH     { $fetches++; $_[0][0] }
    sub STORE     { $stores++;  $_[0][0] = $_[1] }

    package RT57012_TIE_A;

    sub TIEARRAY  { bless [] }
    sub FETCH     { $fetches++; $_[0][0] }
    sub STORE     { $stores++;  $_[0][$_[1]] = $_[2] }

    package main;

    for my $test (@tests) {
	my ($val, $sub_term, $exp_funcs, $exp_fb_funcs,
	    $exp_counts, $exp_taint) = @$test;

	my $tainted_val;
	{
	    # create tainted version of $val (unless its a ref)
	    my $t = substr($^X,0,0);
	    my $t0 = $t."0";
	    my $val1 = $val; # use a copy to avoid stringifying original
	    $tainted_val = ref($val1) ? $val :
			($val1 =~ /^[\d\.]+$/) ? $val+$t0 : $val.$t;
	}
	$tie_val = $tainted_val;

	for my $int ('', 'use integer; ') {
	    $use_int = ($int ne '');
	    my $plain = $tainted_val;
	    my $plain_term = $int . sprintf $sub_term, '$plain';
	    my $exp = eval $plain_term;
	    diag("eval of plain_term <$plain_term> gave <$@>") if $@;
	    is(tainted($exp), $exp_taint,
			"<$plain_term> taint of expected return");

	    for my $ov_pkg (qw(RT57012_OV RT57012_OV_FB)) {
		# the deref ops don't support fallback
		next if $ov_pkg eq 'RT57012_OV_FB'
			and  not defined $exp_fb_funcs;
		my ($exp_fetch_a, $exp_fetch_s, $exp_store) =
		    ($ov_pkg eq 'RT57012_OV' || @$exp_counts < 4)
			? @$exp_counts[0,1,2]
			: @$exp_counts[3,4,5];

		tie my $ts, 'RT57012_TIE_S', $ov_pkg;
		tie my @ta, 'RT57012_TIE_A';
		$ta[0]    = bless [ $tainted_val ], $ov_pkg;
		my $oload = bless [ $tainted_val ], $ov_pkg;

		for my $var ('$ta[0]', '$ts', '$oload') {

		    $funcs = '';
		    $fetches = 0;
		    $stores = 0;

		    my $res_term  = $int . sprintf $sub_term, $var;
		    my $desc =  "<$res_term> $ov_pkg" ;
		    my $res = eval $res_term;
		    diag("eval of res_term $desc gave <$@>") if $@;
		    # uniquely, the inc/dec ops return tthe original
		    # ref rather than a copy, so stringify it to
		    # find out if its tainted
		    $res = "$res" if $res_term =~ /\+\+|--/;
		    is(tainted($res), $exp_taint,
			    "$desc taint of result return");
		    is($res, $exp, "$desc return value");
		    my $fns =($ov_pkg eq 'RT57012_OV_FB')
				? $exp_fb_funcs : $exp_funcs;
		    if ($var eq '$oload' && $res_term !~ /oload(\+\+|--)/) {
			# non-tied overloading doesn't trigger a copy
			# except for post inc/dec
			$fns =~ s/^\(=\)//;
		    }
		    is($funcs, $fns, "$desc methods called");
		    next if $var eq '$oload';
		    my $exp_fetch = ($var eq '$ts') ?
			    $exp_fetch_s : $exp_fetch_a;
		    is($fetches, $exp_fetch, "$desc FETCH count");
		    is($stores, $exp_store, "$desc STORE count");

		}

	    }
	}
    }
}

# EOF