Deno•3y ago

What a method prefixed with `#` means?

This is perhaps the stupidest question ever. But I often see method with names prefixed with a

character in typescript. What does it mean? Google does not seems to know either.

example: https://deno.land/std@0.187.0/streams/text_line_stream.ts?source#L40

Andreu Botella•6/13/23, 2:14 PM

It's a private method

crowlKats•6/13/23, 2:20 PM

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/Private_class_fields

Private class features - JavaScript | MDN

Class fields are public by default, but private class members can be created by using a hash # prefix. The privacy encapsulation of these class features is enforced by JavaScript itself.

didiercrunchOP•6/13/23, 3:05 PM

nice, thanks a lot. I was using the keyword.

AapoAlas•6/13/23, 4:44 PM

is TypeScript-level private only, ie. in runtime the property or method is still entirely public and visible there.

is runtime-private as well, and it is actually one of the strongest possible flavours of privateness, eg. private class fields cannot be accessed by sub-classes.

AapoAlas•6/13/23, 4:45 PM

In short: There's a time and place for both.