Attributes

Named entities in Perl—variables and functions—can have additional metadata attached in the form of attributes. These attributes are arbitrary names and values used with certain types of metaprogrammingWriting programs to write programs for you is known as metaprogramming or code generation..

Declaration of attributes

Attribute declaration syntax is awkward, and using attributes effectively is more art than science. Most programs never use them, but they offer clarity and maintenance benefits when used well.

A simple attribute is a colon-preceded identifier attached to a declaration:

my $fortress

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