If the intent is to find the first entry with a truthy value for the `requestFrame` property, then the proposal is `array.find(.requestFrame)`. If the "wildcard" syntax is used, then it would be `array.find(?.requestFrame)`.
On Thu, Jun 27, 2019 at 5:30 PM guest271314 <guest271...@gmail.com> wrote: > How can the Selector/Select Expression be used with > `Array.prototype.find()`? What happens when the property is not defined? > > For example using the same code for more than one browser > > ``` > const stream = [canvasStream, videoTrack].find(({requestFrame: _}) => _); > ``` > > the property `requestFrame` is either defined or not defined at > ```canvasStream``` or ```videoTrack``` depending on the implementation. > Although the assigned variable can be reduced to 1 character at > destructuring assignment, there is still the redundancy of writing ```_``` > again on the right side of ```=>```. > > If the property is not found, is the result ```undefined```? > Since `.prop` is defined to be identically semantically to `o => o.prop`, yes, the function `.prop` applied to an object with no property named `prop` returns `undefined`.
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