Why there are 2 different syntax of casting in typescript?

Question

As long as I know, there are 2 type of syntax to cast in Typescript.

1. Just using < and > to cast

   const a = <A>b;
   

2. Using as statement to cast

   const a = b as A;
   

I guess generated code of 1 or 2 is completely same. And, there were no such a syntax to use as statement when I started to use Typescript. I guess as is new syntax in typescript.

But, there should be something reason to make new syntax. Why they needed these syntax? Is there something inconvenient if there was only 1 cast syntax?

Answer 1

As described here

Originally the syntax that was added was <foo>.
...

However there is an ambiguity in the language grammar when using <foo> style assertions in JSX:

var foo = <string>bar;
</string>

Therefore it is now recommended that you just use as foo for consistency.