Error on combination of oneTime & signal binding behavior

[genadis]

When trying to use onTime with signal binding as follows:

<div>${date | fromNow & oneTime & signal:'my-date-signal'}</div>

an error is thrown:

Unhandled promise rejection Error: One-time bindings cannot be signaled

It is useful as explained in example in aurelia-binding-behaviors
"Value converter that uses the current time to convert a record's datetime to a "time ago" value: posted ${postDateTime | timeAgo}. The moment this binding expression is evaluated it will correctly result in posted a minute ago. As time passes, it will eventually become inaccurate..."

So we can use signal to reavaluate the postDateTime that doesn't change.

From my understanding the signal is complementary to the binding and doesn't replace it.
I find it many times useful to manually reevaluate, so oneTime & signal seems like natural solution.

Is there a reason they cannot work together?

Thanks

[EisenbergEffect]

@jdanyow Isn't a signal automatically a one-time binding? How should this be handled.

[jdanyow]

The combination of signal + one-time was intentionally disabled:

the signal binding behavior is not applicable to one-time bindings. Currently there is no reason to not support one-time bindings but I'm afraid supporting one-time bindings will prevent us from further optimizing one-time binding scenarios.
#126 (comment)

Time to reconsider this limitation... binding perf refactoring is complete. It should be safe to remove this check and allow one-time + signal.

Thoughts?

[EisenbergEffect]

Obviously, the fix is simple. You are the binding expert. It's your call.

[jdanyow]

Will add some tests and get this into the next release.

[EisenbergEffect]

Beautiful :)

[genadis]

works like a charm, Thanks!

[genadis]

It worked for the above case, but not with repeat.for:

        <template repeat.for="item of items & oneTime & signal:'my-signal">
          <li>
            <compose view-model.bind="item"></compose>
          </li>
        </template>

The list get's rendered once, If I add an item to items array and invoke my-signal the repeat.for is not re rendered.

Should I open separate issue?

[jdanyow]

please do- the repeat custom attribute handles oneTime differently than regular bindings