Proposal: ArgumentDo

[Jon Purdy]

> ambiguity is bad for humans, not just parsers.

This is not ambiguous. It’s removing the need for a redundant set of
parentheses, whichever way you slice it. Of course, some redundancy is
useful for readability (look at natural language), but you should
really be explicit if you’re arguing from that position.

> perhaps most damningly,
>>
>>
>> f do{ x } do { y }
>
>
> is just reallly really weird/confusing to me

By “weird”, do you mean anything other than “I don’t understand it,
and I blame it”? Can you give an example of how you might misparse it,
as a human reader?

>> It's harder to read than the alternative.
>>
>> Creating a language extension to get rid of a single character is overkill
>> and unnecessary.

It’s only a language extension for backward compatibility. It’s really
fixing a bug in the grammar.

> I'm all in favor of doing engineering work to *improve*
> our parser error messages and suggestions, but not stuff that complicates
> parsing for humans  as well as machines

This would be a simplification of the parser if the bug hadn’t been
standardised originally.