TypeScript has all of these patterns, they are used very frequently and they are necessary because TypeScript tends to be interesting from time to time since its types only exist at compile time, because it compiles to JavaScript, which is a language without types.
TypeScript also allows any as a keyword, which says “I don’t know which type this is and I don’t care”, which still produces valid JavaScript. To get back to typed variables it is necessary to use typeof (or similar constructs like a type guard).
But generic type syntax is a feature exclusive to Typescript while typeof is a JavaScript thing. You’d never get Pie[Pie[T]] as a result from a typeof check. (Please excuse the square brackets; seems like the markdown parser here isn’t quite right and it keeps messing up the angle brackets)
This is likely referring to TypeScript.
TypeScript has all of these patterns, they are used very frequently and they are necessary because TypeScript tends to be interesting from time to time since its types only exist at compile time, because it compiles to JavaScript, which is a language without types.
TypeScript also allows
anyas a keyword, which says “I don’t know which type this is and I don’t care”, which still produces valid JavaScript. To get back to typed variables it is necessary to usetypeof(or similar constructs like a type guard).https://www.typescriptlang.org/docs/handbook/2/typeof-types.html
But generic type syntax is a feature exclusive to Typescript while
typeofis a JavaScript thing. You’d never getPie[Pie[T]]as a result from atypeofcheck. (Please excuse the square brackets; seems like the markdown parser here isn’t quite right and it keeps messing up the angle brackets)Also, it’s
typeof foonottypeof(foo)in js