Creates a new substitution from the sequence of elems.
Returns this substitution where the variable p._1 is updated with the value of p._2.
Returns the combination of this substitution with s
Returns the substitution which is generated by applying s to this substitution.
Returns the term to which the variable v is mapped in this substitution.
Returns the set of variables which are mapped.
Returns the set of variables introduced through the mapping.
Returns true if this substitution is just a renaming and false otherwise.
Returns the number of mappings in this substitution.
Returns this substitution in reversed order.
Returns true if this substitution is a subset of that substitution.
Represents a substitution.
A substitution sigma is a mapping from variables to terms such that x != sigma x for finitely many x only.