When we italicize a word or phrase in here, it usually means you can find it defined elsewhere in the glossary. Think of them as hyperlinks.

accessor methods

A method used to indirectly inspect or update an object’s state (its instance variables).

actual arguments

The scalar values that you supply to a function or subroutine when you call it. For instance, when you call power("puff"), the string "puff" is the actual argument. See also argument and formal arguments.

address operator

Some languages work directly with the memory addresses of values, but this can be like playing with fire. Perl provides a set of asbestos gloves for handling all memory management. The closest to an address operator in Perl is the backslash operator, but it gives you a hard reference, which is much safer than a memory address.


A well-defined sequence of steps, explained clearly enough that even a computer could do them.


A nickname for something, which behaves in all ways as though you’d used the original name instead of the nickname. Temporary aliases are implicitly created in the loop variable for foreach loops, in the $_ variable for map or grep operators, in $a and $b during sort’s comparison function, and in each element of @_ for the actual arguments of a subroutine call. Permanent aliases are explicitly created in packages by importing symbols or by assignment to typeglobs. Lexically scoped aliases for package variables are explicitly created by the our declaration.


The ...

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