Personally I prefer the requirement of spaces; if you require a method to have 
textual operators without spaces then IMO it’s probably not a good place to use 
a textual operator in the first place.

I like the space requirement as it essentially lets textual operators be custom 
keywords, for example the recent thread on striding for loops, we could do the 
following:

        for eachIndex in 1 ..< 10 by 2 { … }

With the “by” defined as a custom operator on Range, rather than defining a new 
keyword or for loop variant (since it’s still essentially a for in loop). It’s 
really just a nicer alternative to: (1 ..< 10).by(2).

> On 28 Mar 2016, at 16:21, Thorsten Seitz via swift-evolution 
> <swift-evolution@swift.org> wrote:
> 
>> Am 08.01.2016 um 09:38 schrieb Jacob Bandes-Storch via swift-evolution 
>> <swift-evolution@swift.org <mailto:swift-evolution@swift.org>>:
>> 
>> I'd be hesitant to support something like this. • is a very natural choice 
>> for a binary operator by itself, and restricting it to require the use of 
>> spaces seems unfortunate.
> 
> What about if • would have to begin and end an operator containing letters?
> 
> x = a •times• b •mod• 8
> 
> This looks more symmetrically (like Haskell’s backticks) and wouldn’t need 
> the restriction to require spaces.
> 
> Or maybe
> 
> x = a ‹times› b ‹mod› 8
> 
> Also easily typeable on a Mac keyboard.
> 
> 
> 
>> Re: free functions vs. methods: why does this matter? Supposing `foo` were 
>> the syntax (bad choice, because it already has another meaning, but bear 
>> with me), then you could disambiguate "a `foo` b" vs "a `self.foo` b" just 
>> as you can with regular function calls.
> 
> Indeed.
> 
> -Thorsten
> 
> 
>> Re: named parameters: there are two clear choices:
>> - Restrict such a syntax to functions without named parameters (seems 
>> acceptable to me).
>> - Ignore parameter names, allowing any binary function to be used 
>> (challenges with disambiguation, which I believe has had some discussion in 
>> the other thread about function names).
>> 
>> This might be a crazy idea, but is it possible to support "a myfunc b" 
>> without any extra delimiters? As far as I can tell, there's currently no way 
>> this could parse as a valid expression, so there's no ambiguity to resolve, 
>> although I imagine it would be hard to make diagnostics work well. I'm not 
>> sure how this would play with precedence, but that hasn't been discussed for 
>> any of the other solutions either.
>> 
>> Jacob Bandes-Storch
>> 
>> On Fri, Jan 8, 2016 at 12:29 AM, Jo Albright via swift-evolution 
>> <swift-evolution@swift.org <mailto:swift-evolution@swift.org>> wrote:
>>> The rationale is the same - the design of Swift really wants operators and 
>>> identifiers to be partitioned into different namespaces.  Violating that 
>>> would make it impossible to parse a swift file without parsing all of its 
>>> imports.  This is a mistake that C made (you have to parse all the headers 
>>> a file uses to reliably parse the file) that we don’t want to replicate in 
>>> Swift.
>> 
>> 
>> 
>> Thanks Chris. I now understand the reasoning for separating the two groups. 
>> I don’t have a background in language creation, so whatever I can learn from 
>> these email lists is awesome. I have already gained a ton of knowledge 
>> following these conversations.
>> 
>> 
>>> Alternative: Reserve one of the operator characters as an operator 
>>> introducer. Everything from that character to the next whitespace is an 
>>> operator name. This would allow non-operator characters in operator names 
>>> while still preserving the strict operator/identifier separation.
>>> 
>>>    // • is the operator introducer character
>>>    infix operator •times …
>>>    infix operator •mod …
>>>    x = a •times b •mod 8
>>> 
>>> Limitations:
>>> You still can't use an unadorned word as an operator name.
>>> You can't use such an operator without whitespace (unlike operators whose 
>>> names use operator characters only). 
>> 
>> 
>> 
>> Oooooo … that is a very cool alternative Greg. Honestly went into this 
>> proposal thinking there was no possibility, but now I have a glimmer of hope.
>> 
>> Using “•” (option + 8 on keyboard) would be great since it is accessible 
>> through key combo, but isn’t widely used in normal expressions.
>> 
>> What is needed to prove worth of such a feature to be added?
>> 
>> 
>>  Nerd . Designer . Developer
>> Jo Albright
>> 
>> 
>> 
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