Language.Haskell.AntiQuoter.Combinators

Several combinators for AntiQuoters, mainly EP related.

Lifted constructors.

varQ :: EP q => Name -> Q q

Generalized varE/varP.

conQ :: EP q => Name -> [Q q] -> Q q

Generalized conP or combination of conE and appE.

litQ :: EP q => Lit -> Q q

Generalized litE/litP.

tupQ :: EP q => [Q q] -> Q q

Generalized tupE/tupP.

listQ :: EP q => [Q q] -> Q q

Generalized listE/listP.

Ignoring

ignore :: AQResult q

An results that does not output anything.

ignorePat :: EP q => AQResult Exp -> AQResult q

Yielding only a result for expressions and ignoring in patterns.

onlyExp :: EP q => AQResult Exp -> AQResult q

Alias for ignorePat.

Yielding only a result for expressions and ignoring in patterns.

ignoreExp :: EP q => AQResult Pat -> AQResult q

Yielding only a result for patterns and ignoring in expressions.

onlyPat :: EP q => AQResult Pat -> AQResult q

Alias for ignoreExp.

Yielding only a result for patterns and ignoring in expressions.

Unsorted

splice :: EP q => String -> Q q

Uses/Binds a variable of the given name.

  splice = varQ . mkName

wild :: EP q => Q Exp -> Q q

Use a wildcard in pattern context and the given expression in expression contexts. Consider for example the folowing constructor

 EX SrcLoc OtherType

When pattern matching the pattern should look like EX _ x, using a wildcard for the source location. On the other hand making an expression should use some result say resulting in EX someSrcLoc x. With the wild function this general quoter can be written as

 con ''EX [wild someSrcLoc', splice "x"]

Assuming that someSrcLoc' :: ExpQ and that its result is of type SrcLoc.

nonsenseP :: EP q => String -> AQResult Exp -> AQResult q

A failing result for patterns, useful for when a the pattern matched by the using functions should never happen when antiquoting patterns.

nonsenseE :: EP q => String -> AQResult Pat -> AQResult q

See nonsenseP but failing on expresions.