<div>Just to throw out some other options: foo(#) and foo(@). </div><div><br></div><div>(And you thought we'd gotten rid of # argument labels! 😉)</div><div><br><div class="gmail_quote"><div>On Wed, Feb 22, 2017 at 11:48 AM David Sweeris <<a href="mailto:davesweeris@mac.com">davesweeris@mac.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><br class="gmail_msg">
> On Feb 22, 2017, at 11:05 AM, Matthew Johnson <<a href="mailto:matthew@anandabits.com" class="gmail_msg" target="_blank">matthew@anandabits.com</a>> wrote:<br class="gmail_msg">
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>> On Feb 22, 2017, at 12:30 PM, David Sweeris <<a href="mailto:davesweeris@mac.com" class="gmail_msg" target="_blank">davesweeris@mac.com</a>> wrote:<br class="gmail_msg">
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>>> On Feb 22, 2017, at 7:48 AM, Matthew Johnson via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="gmail_msg" target="_blank">swift-evolution@swift.org</a>> wrote:<br class="gmail_msg">
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>>> I like this idea. I think you made the right choice of syntax given the alternatives considered. To me `foo(_)` and `foo(:)` equally imply presence of an argument. The former looks like an anonymous (unnamed) argument and the latter includes the colon which only follows an argument. Between the two `foo(:)` is the better choice because it doesn’t look like a pattern as has been pointed out.<br class="gmail_msg">
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>>> I’m going to do a little brainstorming to try and come up with something that works and doesn’t imply an argument at all but suspect I’ll come up empty handed.<br class="gmail_msg">
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>> What about “foo(Void)”? It might be fairly easily confused with “foo(:Void)”, but in practice, how likely is it for someone to declare both `foo()` and `foo(_: Void)`?<br class="gmail_msg">
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> I almost threw out `foo(Void)` and `foo(Never)` as ideas. There is at least one problem with these. We will hopefully eventually get rid of the need to say `.self` in expressions like `Int.self`. If we are able to do that then `foo(Void)` and `foo(Never)` are syntactically valid function calls.<br class="gmail_msg">
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Oh, good point! Hrmm… “foo(#null)”/“foo(#nullary)"? I can’t imagine either of those would ever be valid function calls, and they get the point across (the later more than the former, but it’s more to type). I don’t like that syntax for the name of “shortest” version of the function isn’t shorter than the syntax of the name for other versions of the function, though.<br class="gmail_msg">
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- Dave Sweeris</blockquote></div></div>