从文字派生的新Typescript 类型在分配给简单文字或其他类型时会产生编译错误

为了避免将我输入的所有变量相互混淆，我想通过键入它们来添加额外的安全层，如果我试图将文字数字或另一种类型赋给这个新类型，就会产生编译错误.

你可以把它看作给我的变量一个单位，例如"秒"和"米".它们都是从文字类型"Numbers"派生的，但是我应该不能用一个类型的Meter添加一个变量类型的Second.我也不应该能够将类型为Second的变量赋给另一个类型为Meter的变量.

let length1   =  5 as Meter;
let length2   =  7 as Meter;
let duration1 = 10 as Second;
let duration2 = 11 as Second;

let lengthSum = length1 + length2         // should type lengthSum as Meter and give it a value of 12
let durationSum = duration1 + duration2   // should type durationSum as Second and give it a value of 21

length1 = duration2                // should generate an error
let foo = length1 + duration1;     // should generate an error

通过扩展，我也想对字符串执行同样的操作:

let myBookTitle = "Best title ever" as Title;
let myBookAuthor = "John Doe" as Author;

myBookTitle = myBookAuthor // should generate an error

.

我try 了以下自定义类型:

type Meter = number & { __type: 'meter' };
type Second = number & { __type: 'second' };

它们适用于大多数情况，但忽略了混合加法的情况:

let length1 = 5 as Meter;
let length2 = 10 as Meter;
let duration1 = 2 as Second;
let duration2 = 3 as Second;

length1 = length2; // works as expected
length1 = duration1; // generates an error as expected

let length10 = (length1 + length2) as Meter; // works but is not able to automatically infer the length10 type with the "as Meter"
let length11 = (duration1 + duration2) as Second; //same as above

let length12 = (length1 + duration2) as Second; // Shouldn't allow such addition but does it without any error!!

Would anyone know how to create a new type that covers all my constraints? (I know there are some npm packages that cover specifically the SI units, but that is not what I am looking for. Units are used here as examples; I will need to handle multiple types of différents types outside "simple" units. Thanks.)