Day 2 meeting notes

felix felix8a at
Fri Jul 30 12:06:02 PDT 2010

On 7/29/10 16:55, Oliver Hunt wrote:
> On Jul 29, 2010, at 2:47 PM, Waldemar Horwat wrote:
>> Comprehensions:  To be useful, need to have a bunch of basic helpers
>> such as range(), properties(), values(), etc. with short names that
>> can be used to construct comprehensions.  These will be added to the
>> proposal.
>> Would like to be able to interleave for and if clauses:
>> [x*y for (x in range(...)) if (isprime(x)) for (y in range(x+1...)) if
>> (isprime(y))]
> I keep seeing code like this, I simply don't see it as viable to have "for (.. in ...)" sometimes enumerate property names, and some times enumerate keys, it seems like it could be both confusing and error prone.  esp. given the simplest example: [x for (value in [1,2,3])] you would not get the desired behaviour, unless in comprehensions for(in) behaves differently from everywhere else.
> It seems far better to just define a distinct syntax for enumerating values of an object.

actionscript 3 has
   for (key in a) {}
   for each (val in a) {}

More information about the es-discuss mailing list