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|
#!./perl
BEGIN { unshift @INC, './lib', '../lib';
require Config; import Config;
}
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 unsignificant
);
sub new {
my $foo = $_[1];
bless \$foo;
}
sub stringify { "${$_[0]}" }
sub numify { 0 + "${$_[0]}" } # Not needed, additional overhead
# comparing to direct compilation based on
# stringify
package main;
$test = 0;
$| = 1;
print "1..",&last,"\n";
sub test {
$test++; if (shift) {print "ok $test\n";1} else {print "not ok $test\n";0}
}
$a = new Oscalar "087";
$b= "$a";
# All test numbers in comments are off by 1.
# So much for hard-wiring them in :-)
test ($b eq $a); # 2
test ($b eq "087"); # 3
test (ref $a eq "Oscalar"); # 4
test ($a eq $a); # 5
test ($a eq "087"); # 6
$c = $a + 7;
test (ref $c eq "Oscalar"); # 7
test (!($c eq $a)); # 8
test ($c eq "94"); # 9
$b=$a;
test (ref $a eq "Oscalar"); # 10
$b++;
test (ref $b eq "Oscalar"); # 11
test ( $a eq "087"); # 12
test ( $b eq "88"); # 13
test (ref $a eq "Oscalar"); # 14
$c=$b;
$c-=$a;
test (ref $c eq "Oscalar"); # 15
test ( $a eq "087"); # 16
test ( $c eq "1"); # 17
test (ref $a eq "Oscalar"); # 18
$b=1;
$b+=$a;
test (ref $b eq "Oscalar"); # 19
test ( $a eq "087"); # 20
test ( $b eq "88"); # 21
test (ref $a eq "Oscalar"); # 22
eval q[ package Oscalar; use overload ('++' => sub { $ {$_[0]}++;$_[0] } ) ];
$b=$a;
test (ref $a eq "Oscalar"); # 23
$b++;
test (ref $b eq "Oscalar"); # 24
test ( $a eq "087"); # 25
test ( $b eq "88"); # 26
test (ref $a eq "Oscalar"); # 27
package Oscalar;
$dummy=bless \$dummy; # Now cache of method should be reloaded
package main;
$b=$a;
$b++;
test (ref $b eq "Oscalar"); # 28
test ( $a eq "087"); # 29
test ( $b eq "88"); # 30
test (ref $a eq "Oscalar"); # 31
eval q[package Oscalar; use overload ('++' => sub { $ {$_[0]} += 2; $_[0] } ) ];
$b=$a;
test (ref $a eq "Oscalar"); # 32
$b++;
test (ref $b eq "Oscalar"); # 33
test ( $a eq "087"); # 34
test ( $b eq "88"); # 35
test (ref $a eq "Oscalar"); # 36
package Oscalar;
$dummy=bless \$dummy; # Now cache of method should be reloaded
package main;
$b++;
test (ref $b eq "Oscalar"); # 37
test ( $a eq "087"); # 38
test ( $b eq "90"); # 39
test (ref $a eq "Oscalar"); # 40
$b=$a;
$b++;
test (ref $b eq "Oscalar"); # 41
test ( $a eq "087"); # 42
test ( $b eq "89"); # 43
test (ref $a eq "Oscalar"); # 44
test ($b? 1:0); # 45
eval q[ package Oscalar; use overload ('=' => sub {$main::copies++;
package Oscalar;
local $new=$ {$_[0]};
bless \$new } ) ];
$b=new Oscalar "$a";
test (ref $b eq "Oscalar"); # 46
test ( $a eq "087"); # 47
test ( $b eq "087"); # 48
test (ref $a eq "Oscalar"); # 49
$b++;
test (ref $b eq "Oscalar"); # 50
test ( $a eq "087"); # 51
test ( $b eq "89"); # 52
test (ref $a eq "Oscalar"); # 53
test ($copies == 0); # 54
$b+=1;
test (ref $b eq "Oscalar"); # 55
test ( $a eq "087"); # 56
test ( $b eq "90"); # 57
test (ref $a eq "Oscalar"); # 58
test ($copies == 0); # 59
$b=$a;
$b+=1;
test (ref $b eq "Oscalar"); # 60
test ( $a eq "087"); # 61
test ( $b eq "88"); # 62
test (ref $a eq "Oscalar"); # 63
test ($copies == 0); # 64
$b=$a;
$b++;
test (ref $b eq "Oscalar") || print ref $b,"=ref(b)\n"; # 65
test ( $a eq "087"); # 66
test ( $b eq "89"); # 67
test (ref $a eq "Oscalar"); # 68
test ($copies == 1); # 69
eval q[package Oscalar; use overload ('+=' => sub {$ {$_[0]} += 3*$_[1];
$_[0] } ) ];
$c=new Oscalar; # Cause rehash
$b=$a;
$b+=1;
test (ref $b eq "Oscalar"); # 70
test ( $a eq "087"); # 71
test ( $b eq "90"); # 72
test (ref $a eq "Oscalar"); # 73
test ($copies == 2); # 74
$b+=$b;
test (ref $b eq "Oscalar"); # 75
test ( $b eq "360"); # 76
test ($copies == 2); # 77
$b=-$b;
test (ref $b eq "Oscalar"); # 78
test ( $b eq "-360"); # 79
test ($copies == 2); # 80
$b=abs($b);
test (ref $b eq "Oscalar"); # 81
test ( $b eq "360"); # 82
test ($copies == 2); # 83
$b=abs($b);
test (ref $b eq "Oscalar"); # 84
test ( $b eq "360"); # 85
test ($copies == 2); # 86
eval q[package Oscalar;
use overload ('x' => sub {new Oscalar ( $_[2] ? "_.$_[1]._" x $ {$_[0]}
: "_.${$_[0]}._" x $_[1])}) ];
$a=new Oscalar "yy";
$a x= 3;
test ($a eq "_.yy.__.yy.__.yy._"); # 87
eval q[package Oscalar;
use overload ('.' => sub {new Oscalar ( $_[2] ?
"_.$_[1].__.$ {$_[0]}._"
: "_.$ {$_[0]}.__.$_[1]._")}) ];
$a=new Oscalar "xx";
test ("b${a}c" eq "_._.b.__.xx._.__.c._"); # 88
# Here we test blessing to a package updates hash
eval "package Oscalar; no overload '.'";
test ("b${a}" eq "_.b.__.xx._"); # 89
$x="1";
bless \$x, Oscalar;
test ("b${a}c" eq "bxxc"); # 90
new Oscalar 1;
test ("b${a}c" eq "bxxc"); # 91
# Last test is number 90.
sub last {90}
|
