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Postings from April 2008
First let's get this out of the way:
? = "1" | "2" | "4" | "8",
< = "4" | "8",
Meaning: if you see ? then it used strings and not the numbers.
First observation:
perl -wle 'my $x=4 ;my $y=8 ;print $x | $y;' # prints 12
perl -wle 'my $x="4";my $y="8";print $x | $y;' # prints <
perl -wle 'my $x="4";my $y="8";print 0 | $x | $y;' # prints 12
(which is ok/expected)
Second observation:
#!/usr/bin/perl -l
use Readonly;
Readonly my $RETACT_DO_MARK_FRAUD => 4;
Readonly my $RETACT_DO_EMAIL_CONFIRM => 8;
print $RETACT_DO_MARK_FRAUD|$RETACT_DO_EMAIL_CONFIRM;
print $RETACT_DO_MARK_FRAUD|$RETACT_DO_EMAIL_CONFIRM;
__END__
Output:
<
12
This shows that it first used the string "4" and the string "8" and
after that the number 4 and the number 8.
But I find this somewhat confusing...
perl -wle 'my $x="4";my $y="8";print $x | $y;print $x | $y' # prints
< < and not < 12.
Looking deeper:
perl -wle 'use Tie::Scalar;use base qw/Tie::StdScalar/;tie my $x,
"main", 4;tie my $y, "main", 8;for (1 .. 2) { print $x | $y }'
Also prints < and 12.
Taking Tie::Scalar out of the picture:
perl -wle 'sub TIESCALAR { my $foo = $_[1]; bless \$foo, "main"; };sub
FETCH { ${ $_[0]} } ;tie my $x, "main", 4;tie my $y, "main", 8;for (1
.. 2) { print $x | $y }'
Also prints < and 12.
So could this be a problem with how tie works?
Kind regards,
Bram
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