$var
From Scriptwiki
Returns information about currently set variables, local or set.
$var(variable name [,N])[.value|.local]
- Variable name is a wild card value.
- N tells us we want the Nth matching variable.
- N is 0 by default, and therefore can be used to check for existence without it
- Returns
- Variable name by default
- Value if .value is specified
- If .local is specified, returns $true or $false based on whether or not the matching variable is a local variable