Maintainer | Benedikt Schmidt <beschmi@gmail.com> |
---|---|
Safe Haskell | None |
Subsumption of terms and substitutions.
- compareTermSubs :: LNTerm -> LNTerm -> WithMaude (Maybe Ordering)
- eqTermSubs :: LNTerm -> LNTerm -> WithMaude Bool
- factorSubstVia :: [LVar] -> LNSubst -> LNSubst -> WithMaude [LNSubst]
- canonizeSubst :: LNSubstVFresh -> LNSubstVFresh
- varOccurences :: HasFrees a => a -> [(LVar, Set Occurence)]
Documentation
compareTermSubs :: LNTerm -> LNTerm -> WithMaude (Maybe Ordering)Source
Compare terms t1
and t2
with respect to the subsumption order modulo AC.
eqTermSubs :: LNTerm -> LNTerm -> WithMaude BoolSource
Returns True if s1
and s2
are equal with respect to the subsumption order modulo AC.
Canonical representations for substitutions
canonizeSubst :: LNSubstVFresh -> LNSubstVFreshSource
Returns a substitution that is equivalent modulo renaming to the given substitution.
for testing only
varOccurences :: HasFrees a => a -> [(LVar, Set Occurence)]Source
Returns the variables occuring in t
together with the contexts they appear in.
Note that certain contexts (and variables only occuring in such contexts) are
ignored by this function.
The function is used to guess renamings of variables, i.e., if t is a renaming of s,
then variables that occur in equal contexts in t and s are probably renamings of
each other.