class TermTypeUnifier:
'''Unify the types of free variables.
The resultant unifier ensures that all free variables with a given
name have the same type.
'''
def __init__(self):
self.unifier = TypeUnifier()
def add_terms(self, terms):
all_frees = set()
for term_frees in (term.free_variables() for term in terms):
all_frees.update(term_frees)
for frees in by_name(all_frees).values():
self.unifier.unify_many([free.qtype for free in frees])
def apply(self, term):
for key, value in self.get_substitutions().iteritems():
term = term.substitute_type(value, key)
return term
def get_substitutions(self):
return self.unifier.get_substitutions()
def __init__(self):
self.unifier = TypeUnifier()
