Arborist::NegLookAhead
Inherits Reference / Object
Non-consuming negative lookahead match of e
Constructors
Instance methods
eval(matcher) : ParseTree | Nil
this should return true if the expr does not match, and nil otherwise; do not return false, because nil indicates parse failure
label(label : String) : NegLookAhead
Sourcelabel
Sourcelabel=(label : String | Nil)
Sourcepreorder_traverse(matcher, visit : Expr -> _, visited_nodes : Set(Expr))
Sourceto_s
Returns a nicely readable and concise string representation of this object, typically intended for users.
This method should usually not be overridden. It delegates to
#to_s(IO) which can be overridden for custom implementations.
Also see #inspect.