I have a method modifier like so: 
before 'wafer' => sub{
    my $self = shift;
    if ( ! $self->_wafer_parse_complete ){ $self->_wafer_parse };
    
};

[download]
The _wafer_parse sub has a while loop in it. If I call $obj->wafer( '01' ) a single time, all is well. If I call $obj->wafer( '05' ) a second time with a new value, I get this error: 
Use of uninitialized value in subroutine entry at Class/MOP/Method/Wra
+pped.pm line 47
Can't use string ("") as a subroutine ref while "strict refs" in use a
+t Class/MOP/Method/Wrapped.pm line 47.

[download]
I have found that by changing the while loop to a foreach loop, the problem goes away. I am using the while loop to read through a file, so I don't want to use foreach.
Has anyone else had this problem or know of how to fix this? I am using Moose 0.65 and ActiveState Perl 5.10.0. I tried Google search and supersearch, but I couldn't find anything.
Thanks, David

Update1:
one of the strange things, is that _wafer_parse is only ever called for the first instance becuase it sets the _wafer_parse_complete sub to a true value. Just having the while loop in the sub causes this to die, not actually running the sub twice.

Update2:
The method _wafer_parse is something like this. This fails:
sub _wafer_parse {
    my $self = shift;
    
    open my $FILE, "<", $self->{file};

    while ( <$FILE> ){};
    close $FILE;
}

[download]
If I removed the open command, the subroutine runs fine.

In reply to While Loop in Before Modifier Gives Error by ~~David~~

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