There are, by my unscientific count*, 439 instances in base that use "for ... =", and 653 using "for ... in".
(grep -Ri "for .* =" *.jl | wc -l) On Tuesday, October 27, 2015 at 11:36:01 AM UTC-7, David Anthoff wrote: > > If something like this were to change, it would be good to do it sooner > rather than later -> less code that depends on the syntax that would go > would have been written. So maybe the right way forward for this is to open > an issue suggesting to drop the = variant, discuss it, make a decision and > then live with it, all for the 0.5 cycle. > > > > I don’t feel strongly about this, but for what it’s worth, I’m also a fan > of having only one way to do something like this. > > > > Cheers, > > David > > > > *From:* julia...@googlegroups.com <javascript:> [mailto: > julia...@googlegroups.com <javascript:>] *On Behalf Of *FANG Colin > *Sent:* Tuesday, October 27, 2015 11:20 AM > *To:* julia...@googlegroups.com <javascript:> > *Subject:* Re: [julia-users] Re: For loop = or in? > > > > Julia tries to attract people from Python & R, which use `in`. As for > matlab, it is not a direct competitor. > > > > Anyway, I think we only need 1 of the 2. "There should be one-- and > preferably only one --obvious way to do it." > > > > Maybe enhance the documentation for the time being. > > > > > > On 27 October 2015 at 16:38, Glen O <gjo...@gmail.com <javascript:>> > wrote: > > "When calculating a Fibonacci number, we have to apply F_n=F_(n-1)+F_(n-2) > repeatedly. So to find F_6, we apply the equation for n equals 3 through > 6". Writing it as "for n in 3 through 6" or "for n in the range 3 through > 6" wouldn't make nearly as much sense. > > > > As I said, for general iterables, like vectors, the "in" keyword makes > more sense. But when you're talking about a counter variable, equals makes > a much more natural expression - you're not really constructing the range > object, you're just telling the program you want the counter to start at > the first value, and increment until it reaches the second value. > > On Wednesday, 28 October 2015 02:23:54 UTC+10, Tom Breloff wrote: > > It definitely makes sense for a range. > > > > Sorry... gotta disagree... mathematical set notation is more appropriate, > especially for scientific computing. This is coming from a former matlab > user, btw, so it's not like I was confused by the syntax. The "for i = > 1:5" syntax is actually more reminiscent of C: "for (int i=1; i<=5; i++)", > and I'm guessing that the syntax originated more from that rather than > scientific concepts. > > > > On Tue, Oct 27, 2015 at 11:58 AM, feza <moham...@gmail.com> wrote: > > +1 @Tom Breloff . > I was confused about this when starting out. Comparing `for i in 1:3` vs > `for i = 1:3`, even though I regularly use matlab if you think about it > for `i = 1:10` doesn't really make a lot of sense. It would be nice if it > was just one way as opposed to the confusion about whether = or in should > be used. > > On Tuesday, October 27, 2015 at 10:26:44 AM UTC-4, Tom Breloff wrote: > > It's harmless, sure, but I would prefer that everyone uses "in" > exclusively so that there's one less thing to waste brainpower on. You > don't say "for each x equals the range 1 to n", you say "for each x in the > range 1 to n". I don't think "=" has a place here at all except to allow > copy/pasting of Matlab code (which creates other performance problems > anyways). > > > > On Tue, Oct 27, 2015 at 10:04 AM, Stefan Karpinski <ste...@karpinski.org> > wrote: > > My general approach is to only use = when the RHS is an explicit range, as > in `for i = 1:n`. For everything else I use `for i in v`. I would be ok > with dropping the = syntax at some point, but it seems pretty harmless to > have it. > > > > On Tue, Oct 27, 2015 at 8:56 AM, FANG Colin <coli...@gmail.com> wrote: > > Thank you. In that case I will happily stick with `in`. > > > > On Monday, October 26, 2015 at 8:43:22 PM UTC, Alireza Nejati wrote: > > There is no difference, as far as I know. > > > > '=' seems to be used more for explicit ranges (i = 1:5) and 'in' seems to > be used more for variables (i in mylist). But using 'in' for everything is > ok too. > > > > The '=' is there for familiarity with matlab. Remember that julia's syntax > was in part designed to be familiar to matlab users. > > > On Tuesday, October 27, 2015 at 8:26:07 AM UTC+13, FANG Colin wrote: > > Hi All > > > > I have got a stupid question: > > > > Are there any difference in "for i in 1:5" and "for i = 1:5"? > > > > Does the julia community prefer one to the other? I see use of both in the > documentations and source code. > > > > Personally I haven't seen much use of "for i = 1:5" in other languages. > > > > Thanks. > > > > > > > > >
