Convert from/to native streams? about web-streams-polyfill HOT 3 CLOSED

Some more thoughts on this...

Right now, the polyfill always replaces the global stream implementations. However, if the native implementation were fully spec-compliant, the polyfill should detect this and simply use the native implementation. (At the moment, Chrome 68 is the closest to full compliance, supporting everything except for readable byte streams.)

If the polyfill would re-export the native implementation, then we can't provide ReadableStream.from without mutating the global ReadableStream. Therefore, we should not use static utility methods.

from web-streams-polyfill.

Looks like the spec is planing on adding ReadableStream.from(iterable) now as well.

It could serve as a grate utility to convert the polyfill stream to/from a native one (until you are using native streams - #20)

maybe could have two implementation in the meanwhile?

• window.ReadableStream.from(iterable) // converts iterable to native
• polyfill.ReadableStream.from(iterable) // converts iterable to polyfilled version

all doe the later one would quickly be obsolete when you are using native streams.
the native ReadableStream would also need asyncIterable to work...

from web-streams-polyfill.

Good idea! 👍

Indeed, if ReadableStream.from() becomes a thing, the polyfill can provide a version which also handles conversions. Aside from accepting an (async) iterable, it could also accept a native ReadableStream (even if the native stream is not async iterable itself).

I'll keep it in mind when I (eventually) get to this. Right now, I'm keeping an eye on the ongoing work for converting the spec to WebIDL, in particular on the functional changes that will be needed for the polyfill... 👀

from web-streams-polyfill.