Re: (Ovid) Re: Autoload'ed class method calls

Ovid, not sure that hackdaddy has got it wrong. His code is the AUTOLOAD sub, not the constructor. I presume he will be supplying his own new sub so that AUTOLOAD will not be called on construction.

More importantly, he needs to declare $AUTOLOAD in package namespace, with

use vars qw($AUTOLOAD);
[download]

our $AUTOLOAD;
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The rest seems to go through use strict 'refs'OK.

Update: Ovid I am humbled! It's interesting how staring at a piece of code can lead you to wrong conclusions (in my case exacerbated by lack of sleep and coffee).

It also shows what a snarfy beast AUTOLOAD can be. I've written pseudo-methods in AUTOLOAD myself, but usually solved problems like hackdaddy's by stepping through with the debugger.

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(Ovid) Re(3): Autoload'ed class method calls by Ovid (Cardinal) on Apr 05, 2002 at 18:46 UTC
Read through his code and error message again. hackdaddy already has `$AUTOLOAD` declared properly, otherwise the first method call would fail, but according to hackdaddy, it's successful. However, read through the text of the actual error message. `Can't use string ("WM::Install::Table::ArchiveTbl") as a HASH ref whil +e "strict refs" in use at /u08/pkg/wms/wmcmtools/modules/WM/Install/Table/ArchiveTbl.pm line +192.` [download] Now look at first few lines of the autoload. `sub AUTOLOAD { my ($self, $newval) = @_; $AUTOLOAD =~ /.::get(_\w+)/ and $self->_accessible($1) and return $self->{$1};` [download] As you can see, the return statement (`return $self->{$1}`) is attempting to use `$self` as a hashref. Since the error messsage shows that the programmers is trying to use the package name as a hashref, we clearly have the package name and not the object* being passed as the first argument to `AUTOLOAD`. I was using a generic constructor to illustrate how the first argument could be a package name instead of an object, as expected. Cheers, Ovid PS: I'm also a Terry Pratchett fan (I'm assuming that's what your nick refers to). Join the Perlmonks Setiathome Group or just click on the the link and check out our stats.	[reply] [d/l] [select]

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(Ovid) Re(3): Autoload'ed class method calls
by Ovid (Cardinal) on Apr 05, 2002 at 18:46 UTC

Read through his code and error message again. hackdaddy already has $AUTOLOAD declared properly, otherwise the first method call would fail, but according to hackdaddy, it's successful. However, read through the text of the actual error message.

Can't use string ("WM::Install::Table::ArchiveTbl") as a HASH ref whil
+e "strict refs" in use 
at /u08/pkg/wms/wmcmtools/modules/WM/Install/Table/ArchiveTbl.pm line 
+192.
[download]

Now look at first few lines of the autoload.

sub AUTOLOAD {
    my ($self, $newval) = @_;
    
    $AUTOLOAD =~ /.*::get(_\w+)/
        and $self->_accessible($1)
        and return $self->{$1};
[download]

As you can see, the return statement (return $self->{$1}) is attempting to use $self as a hashref. Since the error messsage shows that the programmers is trying to use the package name as a hashref, we clearly have the package name and not the object being passed as the first argument to AUTOLOAD. I was using a generic constructor to illustrate how the first argument could be a package name instead of an object, as expected.

Cheers,
Ovid

PS: I'm also a Terry Pratchett fan (I'm assuming that's what your nick refers to).

Join the Perlmonks Setiathome Group or just click on the the link and check out our stats.

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