strawman for the := operator

Brendan Eich brendan at
Thu Aug 9 11:35:58 PDT 2012

Allen Wirfs-Brock wrote:
> On Aug 8, 2012, at 6:14 PM, Brendan Eich wrote:
>> No problem. For anyone used to Pascal or Ada, or familiar with Go, := could indeed be a speedbump.
> (or Smalltalk, ;-)
> But not a big speed-bump. For a Pascal programmers moving directly to ES without any exposure to a C-syntax language, I'm pretty sure that  =/:= confusion isn't going to be the biggest hurdle they will have to deal with.

It's not just old programmers coming out of hypersleep (Ada is still 
used, but nm). The := spelling by itself is close to =, and Doug indeed 
thought it was a workalike. But it's really not.

To switch metaphors from speedbumps, there's smoke. I am not as 
confident as you that there is no fire.

I think it is pretty optimistic to suppose that some day down the road 
when := support is in all target browsers and runtimes, the convenience 
of := will mean developers choose it where they would otherwise choose = 
instead of using Object.defineProperty. They have to know they're 
defining not assigning. The convenience of = or inconvenience of 
Object.defineProperty doesn't enter into that "have to know" condition 
or whether it is satisfied.

People will always prefer = if there's confusion about assigning vs. 
defining, even with :=. Assignment is the "obvious thing".


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