domenic at domenicdenicola.com (2013-09-18T18:54:28.313Z)
On Sep 6, 2013, at 11:56 AM, Brendan Eich wrote: > On that note, if we had generator arrows, why not allow yield in an expression-body. That would be ok, but without an expression level looping construct, you can't do anything very interesting with it. So that leads back to using a generator comprehension and the sort of confusing stuff in the second part of my previous reply.
On Sep 6, 2013, at 11:56 AM, Brendan Eich wrote: >> Allen Wirfs-Brock <mailto:allen at wirfs-brock.com> >> September 6, 2013 11:48 AM >> On Sep 6, 2013, at 11:18 AM, Brendan Eich wrote: >> >>>> Allen Wirfs-Brock<mailto:allen at wirfs-brock.com> >>>> September 6, 2013 11:01 AM >>>> >>>> Almost as good, a arrow function with a generator comprehension as its expression body. For example, a factory for a generator with a lexical this binding: >>>> >>>> c => (for (p of c) if (p in this) this[p]) >>>> >>>> not much different from a hypothetical generator arrow function and arguably better : >>>> c *=> {for (p of c) if (p in this) yield this[p]} >>> There would be no explicit |yield| in the second example, though. (|yield| is an error in any arrow body.) >> >> why no |yield|? Note that I wrote a { } body for the generator arrow function body, rather than an expression body and that generator functions use explicit |yield| in their bodies. > > Sorry, brain-fart. You're right. > > On that note, if we had generator arrows, why not allow yield in an expression-body. That would be ok, but without an expression level looping construct, you can't do anything very interesting with it. So that leads back to using a generator comprehension and the sort of confusing stuff in the second part of my previous reply. Allen