Parenthesis around if/for/while condition is not necessary

[Basile B.]

On Saturday, 23 June 2018 at 06:18:53 UTC, user1234 wrote:
> On Saturday, 23 June 2018 at 05:09:13 UTC, aedt wrote:
>> On Saturday, 23 June 2018 at 04:45:07 UTC, user1234 wrote:
>>> On Saturday, 23 June 2018 at 01:27:30 UTC, aedt wrote:
>>>> for line in stdin.lines() {}
>>>>
>>>> if condition {}
>>>>
>>>> while condition {}
>>>>
>>>> for init; condition; op {}
>>>>
>>>>
>>>> What's the rationale of keeping the requirement that the 
>>>> condition of if/for/while must be wrapped with a parenthesis 
>>>> (other than keeping parser simple)? Modern languages have 
>>>> already dropped this requirement (i.e. Rust, Nim) and I 
>>>> don't see any reason not to do so.
>>>
>>> There is this case that requires parens:
>>>
>>>     if a && b c;
>>>
>>> Is there a missing && or not ? It seems obvious for a human 
>>> but compiler parsers are "apparatchiks", i.e rules are rules. 
>>> That being said this would work by allowing parens for 
>>> disambiguation.
>>
>> Same thing as the following"
>> return a && b;
>>
>> I'm not saying to drop parens completely, I'm saying why is it 
>> not optional. D seems to have no problem with x.to!string or 
>> std.lines
>
> I agree that this would be in adequation with certain stuff of 
> the D syntax, such as parens-less single template parameter. 
> Someone has to make a DIP for this

Maybe but this is a simple parser thing. For example after 
reading the discussion here i have tested the idea in my toy 
programming language 
(https://github.com/BBasile/styx/commit/83c96d8a789aa82f9bed254ab342ffc4aed4fd88) and i believe that for D this would be as simple ( < 20 SLOC, w/o the tests).

> otherwise we're good for one of this sterile NG discussion 
> leading to nothing, i.e intellectual mast... well guess the 
> word.

I'm tempted to try this in DMDFE. Change is simple enough so that 
if it get rejected no much time is lost.