Type checking for typescript

Typescript When types are incompatible, there will be a type checking mechanism to avoid type errors

//  below ：number Namely ts Unique type annotations   Used to control the type checking of variables 

let num:number = 888888;



num=420;

In this way, we can make js This weakly typed language performs strong type checking and then generates more rigorous logic js file , In order to improve the js Logical rigor of

Test it out , You will find that strict type checking is involved in the coding process