Method typeCheck

src/chap14/TypeChecker.java:133–148

(TypeEnv tenv)

        protected TypeEnv bodyEnv;
        public DefStmntEx2(List<ASTree> c) { super(c); }
        public TypeInfo typeCheck(TypeEnv tenv) throws TypeException {
            TypeInfo[] params = ((ParamListEx2)parameters()).types();
            TypeInfo retType = TypeInfo.get(type());
            funcType = TypeInfo.function(retType, params);
            TypeInfo oldType = tenv.put(0, index, funcType);
            if (oldType != null)
                throw new TypeException("function redefinition: " + name(),
                                        this);
            bodyEnv = new TypeEnv(size, tenv);
            for (int i = 0; i < params.length; i++)
                bodyEnv.put(0, i, params[i]);
            TypeInfo bodyType
                = ((ASTreeTypeEx)revise(body())).typeCheck(bodyEnv);
            bodyType.assertSubtypeOf(retType, tenv, this);
            return funcType;
        }
    }
    @Reviser
    public static class ParamListEx2 extends TypedEvaluator.ParamListEx {