| Type | Character | Example | Is a name for |
|---|---|---|---|
| Scalar | $ | $cents | A number (int or float) or string or reference |
| Array | @ | @large | A list of values, keyed by number; zero based: @large[0] |
| Hash | % | %stuff | A group of values, keyed by string; a stuff of key is value: %stuff{key} |
| Subroutine | & | &how | A callable chunk of perl code |
| Typeglob | * | *struck | Everything named struck |
| Reference | \ | \ANY | Reference to ANY, e.g. \%stuffi, or \@ary |
To assign a list of values to an array assign a comma sepatrated
list in parenthesis, e.g.:
@home = ("couch", "chair", "table");
Can be in an assignment, e.g. following is a swap:
($potato, $chip)={$chip, $potato);
Can do a push or pop to an array (at high end).
When evaluated, a typeglob produces a scalar values that represents all the objects of that name, including any scalar, array, or hash varaiable, as well as any filehandle, format, or subroutine. When assigned to, a typeglob sets up its own name to be an alias for whatever typeglob value was assigned to it.
To pass more than one array or hash into or out of a function and maintin
their integrity, use an explict pass by reference:
@gunk=add_arys(\@a1, \@a2, \@3);
| Construct | Meaning |
| $days | simple scalar value $days |
| $days[28] | 29th element of array @days |
| $days{'Feb'} | "Feb" value from hash %days |
| $#days | Last index of array @days |
| $days->[28] | 29th element of array pointed to by reference $days |
| Construct | Meaning |
| @days | same as ($days[0], $days[1], ..., $days[n]) |
| @days[3, 4, 5] | same as ($days[3], $days[4], $days[5]) |
| @days[3..5] | same as ($days[3], $days[4], $days[5]) |
| @days{'Jan', 'Feb'} | same as ($days{'Jan'}, $days{'Feb'}) |
| Construct | Meaning |
| %days | (Jan => 31, Feb => $leap ? 29 : 28, Mar => ...) |