In standard Typescript, you can make an arrow function generic by declaring the type variable before the arguments:
1const identity = <T>(arg: T): T => arg;
However, if you try this in a React
.tsx file, the compiler tries to parse the type variable as a JSX tag:
Typescript's compiler error.
To help the compiler know that this is actually a generic type variable, put a comma (
,) after the type variable:
1// Note the comma 👇 2const identity = <T,>(arg: T): T => arg;