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#  Chapter 15Perl Quick Reference ## 15.3 Variables

\$var

A simple scalar variable.

\$var

29th element of array @var.

\$p = \@var

Now \$p is a reference to array @var.

\$\$p

29th element of array referenced by \$p.

Also, \$p->.

\$var[-1]

Last element of array @var.

\$var[\$i][\$j]

\$j-th element of \$i-th element of array @var.

\$var{'Feb'}

A value from hash (associative array) %var.

\$p = \%var

Now \$p is a reference to hash %var.

\$\$p{'Feb'}

A value from hash referenced by \$p.

Also, \$p->{'Feb'}.

\$#var

Last index of array @var.

@var

The entire array; in a scalar context, the number of elements in the array.

@var[3,4,5]

A slice of array @var.

@var{'a','b'}

A slice of %var; same as (\$var{'a'},\$var{'b'}).

%var

The entire hash; in a scalar context, true if the hash has elements.

\$var{'a',1,...}

Emulates a multidimensional array.

('a'...'z')[4,7,9]

A slice of an array literal.

pkg::var

A variable from a package, e.g., \$pkg::var, @pkg::ary.

\object

Reference to an object, e.g., \\$var, \%hash.

*name

Refers to all objects represented by name.

*n1 = *n2 makes n1 an alias for n2.

*n1 = \$n2 makes \$n1 an alias for \$n2.

You can always use a { block } returning the right type of reference instead of the variable identifier, e.g., \${...}, &{...}. \$\$p is just a shorthand for \${\$p}. 