Calling a method from class / subclass?

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: Calling a method from class / subclass? by merlyn (Sage) on Oct 05, 2007 at 14:37 UTC
I don't believe this code will do anything useful. It will assign a value to a variable literally named `$__PACKAGE__::myLog`, which would be a very strange thing, as it would be no different from assigning to (again picking an arbitrary string) `$__WOOHOO__::myLog`. It's a variable in the package called __PACKAGE__, not a variable in the current package. __PACKAGE__ as a special token works only when it is not part of a larger string or construct. Perhaps what they really wanted was: `{ no strict; ${__PACKAGE__ . "::mylog"} = ...; }` [download] which would make more sense, making $mylog in the current package set to a value. -- Randal L. Schwartz, Perl hacker Update: Of course, I now realized I could have simply used `${"mylog"} = ...` for that assignment. What I did was overkill. :)	[reply] [d/l] [select]
Re: Calling a method from class / subclass? by arkturuz (Curate) on Oct 05, 2007 at 08:44 UTC
`get_logged()` is a method of `InLog` which can be a subclass of `Log` but not neccesarily since we don't have the rest of the code. ~~Basically, this line assignes to a current package variable named $myLog the value of `Log::InLog->get_logged()`~~ For more information read the following documentation: perlmod and perlboot Update: see merlyn's explanation here Re: Calling a method from class / subclass? Time for me to buy a better glasses :)	[reply] [d/l] [select]
Re: Calling a method from class / subclass? by Gangabass (Vicar) on Oct 05, 2007 at 08:32 UTC
Perl gives us the ``__PACKAGE__'' constant which contains the name of the current package.	[reply]
Re: Calling a method from class / subclass? by moritz (Cardinal) on Oct 05, 2007 at 09:19 UTC
This line calls `get_logged()` in the package `Log::InLog` with the package name as the first parameter. ~~The result is assigned to the variable `$mylog` in the current package.~~ See Re: Calling a method from class / subclass? for the assignment target Perl 6 in German	[reply] [d/l] [select]
Re: Calling a method from class / subclass? by Anonymous Monk on Oct 05, 2007 at 08:49 UTC
One addition: `$__PACKAGE__::mylog=Log::Log4perl->get_logger();` In this line of code; Log::Log4perl is a module of CPAN that generates the log files during runtime Now as _PACKAGE_ contains the current package name then what mylog ($PACKAGE::mylog) is for. Is this for calling a variable named mylog from class in _PACKAGE_? Again, why Log::Log4perl is assigned to _PACKAGE_::mylog?? What does this mean?	[reply] [d/l]
Re^2: Calling a method from class / subclass? by arkturuz (Curate) on Oct 05, 2007 at 09:10 UTC
Quote: what mylog ($PACKAGE::mylog) is for To store the value you need variable name: that's `$mylog`. To store it in the current package, you can use `$__PACKAGE__::mylog`. Quote: Again, why Log::Log4perl is assigned to _PACKAGE_::mylog?? What does this mean? It could mean a number of things. One of them could be that author of the code wants a package global variable (variable that is global in the package defined) to be accessed from outside of the package.	[reply] [d/l] [select]