Perl Variables

Built-in Variable Types

The built-in variables types that Perl 5 supports include:

Scalars
Arrays, or Lists
Associative Arrays, or Hashes
Hard and Symbolic References and Typeglobs
File Handles
Special Variables

Scalar and Array Contexts

If a function returns an array and the left-hand side of the equals sign is an array, it is an array context. If the left-hand side is a scalar, it is a scalar context. For example, if we use the built-in function "grep()" to scan an array for a regular expression, and use it in an array context, as in: # @source_code is an array that hold the contents of a file, # each line per array element @matches = grep (/;$/, @source_code);

we would end up with an array "@matches" that holds what grep found. Now if we use it in a scalar context, as in:

# @source_code is an array that hold the contents of a file, # each line per array element $num_matches = grep (/;$/, @source_code);

instead, we get the number of times grep found a match.

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Last Modified: $Date: 1997/05/02 07:17:52 $