Proposal: ArgumentDo

Carter Schonwald carter.schonwald at
Thu Jul 7 22:40:52 UTC 2016

Can you walk me through how this simplifies the grammar etc in concrete
compare contrast or what the diffs between the grammar and associated
engineering would be?

I don't see how it simplifies the grammar, but I could be a bit obtuse.

That aside, I'm also a bit fuzzy on the other claim, that this change will
simplify post parsing engineering,
On Jul 7, 2016 4:47 PM, "Jon Purdy" <evincarofautumn at> wrote:

> > 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.
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