teramako Reporter
	Description • 12 years ago

ECMA-357(E4X) is deprecated.
We should use for-of statement instead of for-each statement

	Justin Dolske [:Dolske]
	Comment 1 • 12 years ago

Bug 737792 did this on the browser side.

Will need to look at this a bit carefully: for-each works on both plain objects and arrays (although one should avoid using it with arrays), whereas for-of only works on arrays.

Quick test because I always confuse these forms... :/

for each (let a in { a:1, b:2 })  --> 1,2
for      (let a of { a:1, b:2 })  --> Exception: not iterable
for      (let a in { a:1, b:2 })  --> a,b

for each (let a in ["a", "b"])  --> a,b
for      (let a of ["a", "b"])  --> a,b
for      (let a in ["a", "b"])  --> 0,1

	teramako Reporter
	Comment 2 • 12 years ago

How about

for (let [, v] of Iterator({ a: 1, b: 2}))  --> 1, 2

	Dão Gottwald [:dao]
	Comment 3 • 12 years ago

(In reply to teramako from comment #2)
> How about
> 
> for (let [, v] of Iterator({ a: 1, b: 2}))  --> 1, 2

Is for-each support going to be dropped? If not, I'd rather keep using it in such cases. Otherwise I'd use for-in with an extra assignment rather than what you propose.

	teramako Reporter
	Comment 4 • 12 years ago

(In reply to Dão Gottwald [:dao] from comment #3)
> (In reply to teramako from comment #2)
> > How about
> > 
> > for (let [, v] of Iterator({ a: 1, b: 2}))  --> 1, 2
> 
> Is for-each support going to be dropped? If not, I'd rather keep using it in
> such cases. Otherwise I'd use for-in with an extra assignment rather than
> what you propose.

Not now, but for-each is defined by ECMA-357 and the specification is deprecated. Then for-each will be non-standard (not de-facto standard at least). Using standardized code as far as possible is better.

	David Bruant
	Comment 5 • 10 years ago

Is this a duplicate of bug 925989 ?