Corrected link: https://bugs.ecmascript.org/show_bug.cgi?id=2737 On 6/13/2014 12:16 AM, André Bargull wrote: >> On Jun 12, 2014, at 2:36 PM, Erik Arvidsson wrote: >> >> >/ Somehow I missed when we decided to allow null/undefined as the iterable value in for-of loops. >> />/ >> />/ The following test passes using the spec algorithms: >> />/ >> />/ var c = 0; >> />/ for (var x of null) { >> />/ c++; >> />/ } >> />/ assert.equal(c, 0); >> />/ >> />/ However, if we get a null value here we are most likely just masking an user bug. >> />/ >> />/ I assume the justification is that for-in allows null here? However, for-of is new syntax and we have the chance to get this right this time around. >> / >> Yup, there was an issue that was reported and fixed fairly recently pointing out that for-of was inconsistent with for-in in this respect. > > for-of statement iteration always ignored undefined/null (always = > since it was added in rev6). I've only requested in [1] to align > for-of iteration in statements and comprehensions to have the same > behaviour w.r.t. undefined/null. > > > [1] https://bugs.ecmascript.org/show_bug.cgi?id=273 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.mozilla.org/pipermail/es-discuss/attachments/20140613/9de6459b/attachment.html>
Corrected link: https://bugs.ecmascript.org/show_bug.cgi?id=2737 On 6/13/2014 12:16 AM, André Bargull wrote: >> On Jun 12, 2014, at 2:36 PM, Erik Arvidsson wrote: >> >> >/ Somehow I missed when we decided to allow null/undefined as the iterable value in for-of loops. >> />/ >> />/ The following test passes using the spec algorithms: >> />/ >> />/ var c = 0; >> />/ for (var x of null) { >> />/ c++; >> />/ } >> />/ assert.equal(c, 0); >> />/ >> />/ However, if we get a null value here we are most likely just masking an user bug. >> />/ >> />/ I assume the justification is that for-in allows null here? However, for-of is new syntax and we have the chance to get this right this time around. >> / >> Yup, there was an issue that was reported and fixed fairly recently pointing out that for-of was inconsistent with for-in in this respect. > > for-of statement iteration always ignored undefined/null (always = > since it was added in rev6). I've only requested in [1] to align > for-of iteration in statements and comprehensions to have the same > behaviour w.r.t. undefined/null. > > > [1] https://bugs.ecmascript.org/show_bug.cgi?id=273 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.mozilla.org/pipermail/es-discuss/attachments/20140613/9de6459b/attachment.html>