FamInst
type FamInstEnvs
tcGetFamInstEnvs
checkFamInstConsistency
tcExtendLocalFamInstEnv
tcLookupDataFamInst
tcLookupDataFamInst_maybe
tcInstNewTyCon_maybe
tcTopNormaliseNewTypeTF_maybe
checkRecFamInstConsistency
newFamInst
makeInjectivityErrors
injTyVarsOfType
injTyVarsOfTypes