Let `with` accept and yield multiple arguments

[mitchlloyd]

Is there a reason that {{#with}} doesn't accept and yield multiple arguments as the let addon does? Has this been discussed before? I'd be happy to write up a quick RFC, but I'm wondering if there is any prior art here.

[nathanhammond]

{{#with}} has been with us since the beginning. Changing its semantics at this point seems likely not in the cards for compat+perf reasons. (Note that I'm not aware of any, but I imagine that both of those problems exist.)

[locks]

Plus, the existence of a community addon to fill the void lessens the necessity to do the change internally.

[rwjblue]

I'm unsure how that addon will be updated to support glimmer 2. The private API's it hacks into do not exist there...

[ghost]

It can be done with a tagless component.

[rwjblue]

@martndemus - Hmmm. Not really. There is no way to splat the input arguments. You could handle the common cases (say 1 to 5 args), but eventually it would fall down.

[mitchlloyd]

Based on the feedback it sounds like we shouldn't change {{#with}}.

• Speculative compatibility issue
• Speculative performance issue
• Already have community addon that will break in next version of Ember
• Can implement tagless component with positional arguments

I've been convinced that changing {{with}} to accept multiple arguments is a bad idea.

So who's going to submit the RFC to remove this feature from Glimmer?

https://github.com/tildeio/glimmer/blob/master/packages/glimmer-runtime/lib/syntax/builtins/with.ts

[rwjblue]

I'm not sure it should be removed...

[mmun]

As pointed out, this feature is implemented so I'm closing the issue.

On a related note, I hope to see an RFC to pull ember-let into core sometime soon. In block form, it's basically a better with unless you are relying on with's falsey value behavior. The inline form is unique and reads quite nicely in my experience.