Purpose
Check if the referenced node has a left sibling in the parse tree.
Syntax
returnedBoolean = variableType("$start"[, number])
returnedBoolean - type: bool
variableType - type: N or X
number - type: int
Returns
Evaluates to 0 if the node has a left sibling and 1 if the referenced node does not have a left sibling.
Remarks
Example
@RULES
@@RULES