DIP 1003 Formal Review

[MysticZach via Digitalmars-d]

On Friday, 26 May 2017 at 01:23:59 UTC, Timon Gehr wrote:
> On 25.05.2017 20:57, MysticZach wrote:
>> struct body {}
>> 
>> interface I {
>>    int foo(int i)
>>    in { assert(i); }
>> 
>>    body bar();
>> }
>> 
>> The ambiguity is fixable by modifying the parser to look ahead 
>> after `body` for `{`. Since virtual interface functions are 
>> not even allowed to have bodies, if it finds `{`, then `body` 
>> should be interpreted as a keyword, and an error issued. In 
>> all other cases `body` should be interpreted as an identifier.
>> 
>> This is not a hard problem, but it is indeed a semantic 
>> ambiguity, so it bears mentioning.
>
> There is no ambiguity, because only one valid interpretation 
> exists.

Well the parser needs to be aware of `body` here both as a 
keyword and as an identifier, and to use context to determine 
which one it is. So to me, that counts as a semantic ambiguity, 
one that is resolved trivially, by a single additional token.

It doesn't seem like it lives up to a more generalized fear of 
having contextual keywords, unless it's like guy 
https://www.youtube.com/watch?v=tgj3nZWtOfA