Agda-2.6.2.1.20220327: A dependently typed functional programming language and proof assistant
Safe HaskellSafe-Inferred
LanguageHaskell2010

Agda.TypeChecking.CheckInternal

Description

A bidirectional type checker for internal syntax.

Performs checking on unreduced terms. With the exception that projection-like function applications have to be reduced since they break bidirectionality.

Synopsis

Documentation

checkType :: MonadCheckInternal m => Type -> m () Source #

Entry point for e.g. checking WithFunctionType.

checkType' :: MonadCheckInternal m => Type -> m Sort Source #

Check a type and infer its sort.

Necessary because of PTS rule (SizeUniv, Set i, Set i) but SizeUniv is not included in any Set i.

This algorithm follows Abel, Coquand, Dybjer, MPC 08, Verifying a Semantic βη-Conversion Test for Martin-Löf Type Theory

checkSort :: MonadCheckInternal m => Action m -> Sort -> m Sort Source #

Check if sort is well-formed.

checkInternal :: MonadCheckInternal m => Term -> Comparison -> Type -> m () Source #

Entry point for term checking.

data Action m Source #

checkInternal traverses the whole Term, and we can use this traversal to modify the term.

Constructors

Action 

Fields

defaultAction :: PureTCM m => Action m Source #

The default action is to not change the Term at all.

infer :: MonadCheckInternal m => Term -> m Type Source #

Infer type of a neutral term.

inferSpine' :: MonadCheckInternal m => Action m -> Type -> Term -> Term -> Elims -> m ((Term, Term), Type) Source #

Returns both the real term (first) and the transformed term (second). The transformed term is not necessarily a valid term, so it must not be used in types.

shouldBeSort :: (PureTCM m, MonadBlock m, MonadError TCErr m) => Type -> m Sort Source #

Result is in reduced form.