Tie
Learn about the tying process in Perl.
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Overview
Where overloading allows us to customize the behavior of classes and objects for specific types of coercion, a mechanism called tying allows us to customize the behavior of primitive variables (scalars,
arrays, hashes, and filehandles). Any operation we might perform on a tied variable translates to a specific method call on an object.
For example, the tie built-in allows the core Tie::File module to treat files as if they were arrays of records, letting us push and pop and shift as we see fit. (tie was intended to use file-backed stores for hashes and arrays, so that Perl could use data too large to fit in available memory. RAM was more expensive twenty years ago.)
The class to which we tie a variable must conform to a defined interface for a specific data type. Read perldoc perltie ...