make on() to return unsubscribe function

[mikhail-angelov]

It will be good if on() function returns unsubscribe function

[developit]

Love the idea! Need to figure out a way to keep this under 200b though ;)

[mjackson]

Save some space by removing the off method?

[developit]

That'd break compat with EventEmitter though. I had wondered if bind() would be shorter.

[loopmode]

Renaming :) list -> l, type -> t

[developit]

@loopmode that's currently done via Uglify as a build step - the 200b size cap we're tracking is actually on the ES3 output.

[mjackson]

@developit Doesn't seem like compat is that important, is it? node's EventEmitter API doesn't even have off. They use removeListener instead.

[developit]

True, I always forget that. I was using WildEmitter prior to writing this, which has on/off. Touché 😉

[tunnckoCore]

@mjackson yea, but it is well-known convention and it feels more natural than returning unsubs from on

[developit]

I've done both and would love to support both if we can squeeze it in. The bind technique should make it pretty cheap 👍

[mikhail-angelov]

I've tried different implementation to reduce size of final lib, but no luck, I'm getting 38 bites more.
Look's like this initial statement (200b) is too strong since initial version was about this size. :(

[dotproto]

Here's a technique for manually creating an unsubscribe function.

let e = mitt();
function handler() {}
e.on('foo', handler);
let unsub = e.off.bind(e, 'foo', handler);

[ajoslin]

I think I found a way, opening a PR.

[developit]

closing in favor of #42