Proposed Enum.one(x) is exactly the same as Enum.at(x, 0). I'm not sure it's worth it intruding a new function just to shave off 2 characters.
Michał. On 26 Apr 2017, 07:26 +0200, Sam Davies <[email protected]>, wrote: > Compare these two: > > `hd Enum.take(collection, 1)` or `collection |> Enum.take(1) |> Enum.at(0)` > > and this: > > `Enum.one(collection)` > > The second seems more readable to me and its purpose is more clear than > either of the first two options. > > On Tuesday, April 25, 2017 at 11:30:02 PM UTC+1, Amos King wrote: > > "Sins of the father." - I prefer consistency to having `take` return two > > different result types. > > > > I think that `Enum.one\2` is a much better idea. I expect the second > > argument to default to nil and allow a default to be passed in. > > > > There is a difference between verbose and explicit. Ruby's each is still > > explicit, but doesn't include the verbosity of a C for loop. I think > > abstractions are fine, and we should consider each one carefully. We need > > to think about their uses and if it should be in the core, an external > > library, or the code using it. Anything that makes it into the core must be > > maintained in the core. In thinking through this like the explicitness of > > the name, but it doesn't buy much more than utilizing `Enum.take\2`. > > > > Amos King > > Owner > > Binary Noggin > > http://binarynoggin.com #business > > http://thisagilelife.com #podcast > > > > ======================================================= > > I welcome VSRE emails. Learn more at http://vsre.info/ > > ======================================================= > > > > > On Tue, Apr 25, 2017 at 4:06 PM, Sam Davies <[email protected]> wrote: > > > > I like `Enum.one/1`. Agree that it's confusing to have `take/1` return > > > > a single element and `take/2` returning a list, although Rails' `take` > > > > works like this. > > > > > > > > If the collection is empty it returns nil naturally. A bang and > > > > non-bang version could work, this would make it work like Ecto's > > > > `one/2` function. > > > > > > > > As for keeping things explicit, if we wanted to be explicit we'd still > > > > be writing for loops in C ;). I like abstractions and a rich set of > > > > functions in the standard library, where it makes sense and doesn't > > > > duplicate functionality. > > > > > > > > > > > > On Sunday, April 23, 2017 at 5:23:38 PM UTC+1, Matt Jadczak wrote: > > > > > I don't think this is needed, but as far as naming suggestions go, > > > > > perhaps `Enum.one/1` would work, as it both indicates that a single > > > > > element is returned, and doesn't necessarily imply ordering like > > > > > `first` would. However, what happens when the Enum is empty? Do we > > > > > need a bang and non-bang version? As others have said, I think that > > > > > keeping this explicit is nicer. You can always add a private helper > > > > > or a function to a project-level utility module if you use this often. > > > > > > > > > > On Saturday, 22 April 2017 18:49:10 UTC+1, Myron Marston wrote: > > > > > > I don't think this would improve Elixir. Elixir favors > > > > > > explicitness over implicitness and fewer keystrokes and the only > > > > > > argument for this seems to be convenience. > > > > > > > > > > > > More worrying, `Enum.take/2` returns a list of items. If there was > > > > > > an `Enum.take/1`, I'd expect it to simply default the number of > > > > > > items taken, but to still return a list (even if it's just a list > > > > > > of one item). But from this thread it sounds like you're wanting > > > > > > an `Enum.take/1` that returns just the first item without it being > > > > > > wrapped in a list. IMO, that would be incredibly confusing. It > > > > > > would lead to different behavior for `&Enum.take/1` and > > > > > > `&Enum.take(&1, 1)` which would be very counter-intuitive. > > > > > > > > > > > > Myron > > > > > > > > > > > > On Saturday, April 22, 2017 at 7:10:27 AM UTC-7, Amos King wrote: > > > > > > > You want to add a default of 1 to Enum.take/2? I personally don't > > > > > > > mind that but I think it takes away from the explicit nature of > > > > > > > the module. I prefer explicitness if we are only saving a few > > > > > > > keystrokes. > > > > > > > > > > > > > > Amos King > > > > > > > Binary Noggin > > > > > > > > > > > > > > On Apr 22, 2017, at 04:12, Sam Davies <[email protected]> wrote: > > > > > > > > > > > > > > > I understand the reasoning. That's why I suggest the name > > > > > > > > `take` NOT the name `first` to make it clear there is no > > > > > > > > implied ordering. > > > > > > > > > > > > > > > > The use case for this is often while working in IEx. I have a > > > > > > > > collection of _somethings_ and I want to see what one > > > > > > > > _something_looks like. I don't care about ordering. > > > > > > > > > > > > > > > > Rails' ActiveRecord has a method called `take` which does much > > > > > > > > the same thing - there is no implied ordering, it just grabs a > > > > > > > > member using some unspecified ordering and returns it. > > > > > > > > > > > > > > > > We already have `take/1` which returns the "first" X elements, > > > > > > > > so it seems logical to me to extend that to `take/0` which > > > > > > > > returns the "first" ONE element. > > > > > > > > > > > > > > > > On Thursday, April 20, 2017 at 5:55:22 PM UTC+1, Allen Madsen > > > > > > > > wrote: > > > > > > > > > Also hd, which takes the head of the list. > > > > > > > > > > > > > > > > > > Allen Madsen > > > > > > > > > http://www.allenmadsen.com > > > > > > > > > > > > > > > > > > > On Thu, Apr 20, 2017 at 12:44 PM, OvermindDL1 > > > > > > > > > > <[email protected]> wrote: > > > > > > > > > > > Two things: > > > > > > > > > > > 1. The `List` module already has a `List.first/1`. > > > > > > > > > > > 2. Not all enumerables have a concept of ordering, like a > > > > > > > > > > > map, so I'm not sure an Enum version of such a thing > > > > > > > > > > > makes conceptual sense? > > > > > > > > > > > > > > > > > > > > > > On Thursday, April 20, 2017 at 10:33:11 AM UTC-6, Sam > > > > > > > > > > > Davies wrote: > > > > > > > > > > > > When working with collections it's often convenient to > > > > > > > > > > > > grab the first element that comes to hand. I find > > > > > > > > > > > > myself writing this a lot: > > > > > > > > > > > > > > > > > > > > > > > > `Enum.take(collection, 1)` or `Enum.at(collection, 0)` > > > > > > > > > > > > > > > > > > > > > > > > How about a function `Enum.take/1` which takes only the > > > > > > > > > > > > collection and returns the "first" value (I avoid > > > > > > > > > > > > naming it `Enum.first/1` since some collections may not > > > > > > > > > > > > have any concept of ordering). > > > > > > > > > > > -- > > > > > > > > > > > You received this message because you are subscribed to > > > > > > > > > > > the Google Groups "elixir-lang-core" group. > > > > > > > > > > > To unsubscribe from this group and stop receiving emails > > > > > > > > > > > from it, send an email to > > > > > > > > > > > [email protected]. > > > > > > > > > > > To view this discussion on the web visit > > > > > > > > > > > https://groups.google.com/d/msgid/elixir-lang-core/69a0953e-07b3-4cc6-8cc0-bee718337ea5%40googlegroups.com. > > > > > > > > > > > > > > > > > > > > > > For more options, visit > > > > > > > > > > > https://groups.google.com/d/optout. > > > > > > > > > > > > > > > > > -- > > > > > > > > You received this message because you are subscribed to the > > > > > > > > Google Groups "elixir-lang-core" group. > > > > > > > > To unsubscribe from this group and stop receiving emails from > > > > > > > > it, send an email to [email protected]. > > > > > > > > To view this discussion on the web visit > > > > > > > > https://groups.google.com/d/msgid/elixir-lang-core/bd395d6b-e64d-41ef-970e-8ac33c0e279c%40googlegroups.com. > > > > > > > > For more options, visit https://groups.google.com/d/optout. > > > > -- > > > > You received this message because you are subscribed to the Google > > > > Groups "elixir-lang-core" group. > > > > To unsubscribe from this group and stop receiving emails from it, send > > > > an email to [email protected]. > > > > To view this discussion on the web visit > > > > https://groups.google.com/d/msgid/elixir-lang-core/9123abef-0f2a-47a8-8e93-69626f9515b2%40googlegroups.com. > > > > > > > > For more options, visit https://groups.google.com/d/optout. > > > -- > You received this message because you are subscribed to the Google Groups > "elixir-lang-core" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/elixir-lang-core/d0ca1a3f-56e4-430b-9ed7-80d225f4d01f%40googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "elixir-lang-core" group. 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