Range - class gi. This class implements an Expression denoting the set of characters in a range. Range Constructs an Expression denoting the set of characters in a range. Repetition - class gi. This class implements an Expression denoting the repetition of a regular language.
Repetition Constructs an Expression denoting the repetition of a regular language.
Singleton - class gi. This class implements an Expression denoting the set containing a string. Singleton Constructs an Expression denoting the set containing a string. UnicodeCategory - class gi. This class implements an Expression denoting the set of characters in a Unicode category.