On Fri, Aug 19, 2005 at 02:06:25PM -0700, Colin Meyer wrote:
> While playing with constant folding and compiler optimizations, I
> noticed something funny about B::Deparse.
>
> It seems to strip the conditionals off of some statements, implying
> that they will always be run. However, they do not get run.
>
>
> Here's my test files:
>
> A.pm:
> package A;
> use constant DEBUG => 1;
> 1;
>
> B.pm:
> package B;
> use constant DEBUG => 0;
> 1;
This is the problem here. When you run it with -MO=Deparse, Deparse
loads the core B.pm so your B.pm is never loaded. If you change the
package name to "J", everything works fine.
> test.pl:
> #!/usr/local/bin/perl
>
> $\="\n";
> use lib '.';
> use A; # DEBUG == 1
> use B; # DEBUG == 0
Try both ways with this addition:
BEGIN { warn "B loaded from $INC{'B.pm'}" }
> use constant AorB => A::DEBUG | B::DEBUG; # 1
> use constant AandB => A::DEBUG & B::DEBUG; # 0
>
> print "A" if A::DEBUG;
> print "B" if B::DEBUG;
> if ( B::DEBUG ) { print "B" }
>
> print "AorB" if AorB;
> print "AandB" if AandB;
>
> perl test.pl:
> A
> AorB
>
> perl -MO=Deparse test.pl:
>
> test syntax OK
> $\ = "\n";
> use lib ('.');
> use A;
> use B;
> use constant ('AorB', 1 | 0);
> use constant ('AandB', 1 & 0);
> print 'A';
> print 'B';
> do {
> print 'B'
> };
> print 'AorB';
> '???';
>
--
Rick Delaney
[EMAIL PROTECTED]
