public static NeuVar?HoistVar(
        this Interpreter <NeuFrame, NeuOperation> interpreter,
        NeuKeywordType keywordType,
        String name,
        NeuOperation value)
    {
        var v = new NeuVar(name, value);

        ///

        interpreter.Hoist(keywordType, name, v);

        ///

        return(v);
    }
    public static NeuVar?CreateVar(
        this Interpreter <NeuFrame, NeuOperation> interpreter,
        String name,
        String?moduleName,
        String?namespaceName,
        String?typeName,
        NeuOperation value)
    {
        if (interpreter.OperationExists(name, moduleName, namespaceName, typeName))
        {
            throw new Exception();
        }

        ///

        var v = new NeuVar(name, value);

        interpreter.VTable.Add(v);

        return(v);
    }