Re^4: need help with Tie::Judy

I'm trying to understand what is happen with the sample code LanX has provided...

The command tie %fruit_color, 'Tie::Judy'; ties the associative array* %fruit_color to the class. From this point on, when %fruit_color is used, instead of the default Perl behaviour, the implementation is handled by Tie::Judy which implements alternative methods to the default methods used by Perl. In this case it does the same thing in a different way.

Is that something like correct?

* I deliberately didn't refer to %fruit_color here as a hash because in this case it is a Judy Array which is not a hash but another example of the same type of storage.

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Re^5: need help with Tie::Judy by LanX (Saint) on Dec 06, 2020 at 02:00 UTC
> Is that something like correct? more or less, yes. `The tie() function binds a variable to a class (package) that will provide the implementation for access methods for that variable. Once this magic has been performed, accessing a tied variable automatically triggers method calls in the proper class. The complexity of the class is hidden behind magic methods calls.` see also perltie#Tying-Hashes > I deliberately didn't refer to %fruit_color here as a hash No it's for sure a "tied hash" in this case implementing a "hash". Both is correct. Perl's generic term for associative arrays is "hash", no matter which implementation is used, so this is still a hash. But a "tied hash" actually only refers to the `%syntax` and connected hash operators. A tied hash may be used for any kind of magic, like e.g. making hash keys case insensitive `$hash{key} eq $hash{KEY}` returning the current time at different places `$time{London}` etc... see also Tie::Hash But - besides providing a different implementations for hashes - it's in my experience mostly only used for syntactic sugar. Most authors prefer providing an explicit OOP solution (like `$time->get("London")` ) and avoid the magic. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply] [d/l] [select]

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Re^5: need help with Tie::Judy
by LanX (Saint) on Dec 06, 2020 at 02:00 UTC

> Is that something like correct?

more or less, yes.

The tie() function binds a variable to a class (package) that will provide the implementation for access methods for that variable. Once this magic has been performed, accessing a tied variable automatically triggers method calls in the proper class. The complexity of the class is hidden behind magic methods calls.