@@ -135,6 +135,7 @@ valueToJs opts m e (IfThenElse cond th el) = JSConditional (valueToJs opts m e c
135135valueToJs opts m e (Accessor prop val) = JSAccessor prop (valueToJs opts m e val)
136136valueToJs opts m e (App val arg) = JSApp (valueToJs opts m e val) [valueToJs opts m e arg]
137137valueToJs opts m e (Abs (Left arg) val) = JSFunction Nothing [identToJs arg] (JSBlock [JSReturn (valueToJs opts m (bindName m arg e) val)])
138+valueToJs opts m e (TypedValue _ (Abs (Left arg) val) ty) | optionsPerformRuntimeTypeChecks opts = let arg' = identToJs arg in JSFunction Nothing [arg'] (JSBlock $ runtimeTypeChecks arg' ty ++ [JSReturn (valueToJs opts m e val)])
138139valueToJs _ m _ (Var ident) = varToJs m ident
139140valueToJs opts m e (TypedValue _ val _) = valueToJs opts m e val
140141valueToJs _ _ _ (TypeClassDictionary _ _) = error "Type class dictionary was not replaced"
@@ -172,6 +173,39 @@ bindNames m idents env = env { names = M.fromList [ ((m, ident), (noType, LocalV
172173 where
173174 noType = error "Temporary lambda variable type was read"
174175
176+
177+-- |
178+-- Generate code in the simplified Javascript intermediate representation for runtime type checks.
179+--
180+runtimeTypeChecks :: String -> Type -> [JS]
181+runtimeTypeChecks arg ty =
182+ let
183+ argTy = getFunctionArgumentType ty
184+ in
185+ maybe [] (argumentCheck (JSVar arg)) argTy
186+ where
187+ getFunctionArgumentType :: Type -> Maybe Type
188+ getFunctionArgumentType (TypeApp (TypeApp t funArg) _) | t == tyFunction = Just funArg
189+ getFunctionArgumentType (ForAll _ ty' _) = getFunctionArgumentType ty'
190+ getFunctionArgumentType _ = Nothing
191+ argumentCheck :: JS -> Type -> [JS]
192+ argumentCheck val t | t == tyNumber = [typeCheck val "number"]
193+ argumentCheck val t | t == tyString = [typeCheck val "string"]
194+ argumentCheck val t | t == tyBoolean = [typeCheck val "boolean"]
195+ argumentCheck val (TypeApp t _) | t == tyArray = [arrayCheck val]
196+ argumentCheck val (Object row) =
197+ let
198+ (pairs, _) = rowToList row
199+ in
200+ typeCheck val "object" : concatMap (\(prop, ty') -> argumentCheck (JSAccessor prop val) ty') pairs
201+ argumentCheck val (TypeApp (TypeApp t _) _) | t == tyFunction = [typeCheck val "function"]
202+ argumentCheck val (ForAll _ ty' _) = argumentCheck val ty'
203+ argumentCheck _ _ = []
204+ typeCheck :: JS -> String -> JS
205+ typeCheck js ty' = JSIfElse (JSBinary NotEqualTo (JSTypeOf js) (JSStringLiteral ty')) (JSBlock [JSThrow (JSStringLiteral $ ty' ++ " expected")]) Nothing
206+ arrayCheck :: JS -> JS
207+ arrayCheck js = JSIfElse (JSUnary Not (JSApp (JSAccessor "isArray" (JSVar "Array")) [js])) (JSBlock [JSThrow (JSStringLiteral "Array expected")]) Nothing
208+
175209-- |
176210-- Generate code in the simplified Javascript intermediate representation for a reference to a
177211-- variable.