Call to arms: lambda-case is stuck and needs your help
cdsmith at gmail.com
Mon Jul 9 18:20:29 CEST 2012
Right, it seems to me that there are basically three reasonable proposals here:
1. "\ of" with multiple arguments. This is consistent with existing
layout, and seems like a nice generalization of lambda syntax.
2. "case of" with a single argument. This is consistent with existing
layout, and seems like a nice generalization of sections.
3. "\" introducing layout, possibly with changes to layout rules. A
much more intrusive change, but it does have a nice efficiency to it.
Either of the first two would be fine. For that matter, they could
even *both* be done -- with #2 being a shorthand to avoid parentheses
-- without seeming too redundant to me. I tend to see the third
option as too intrusive and dangerous, but I can see the argument for
doing it. Given that we have these three options, I really don't see
the benefit to "\ case" or similar ideas, which complicate layout
rules for little reason, and mix syntax in such a way that it's
difficult for me at least to even predict whether parentheses are
On Mon, Jul 9, 2012 at 8:52 AM, Twan van Laarhoven <twanvl at gmail.com> wrote:
> On 09/07/12 14:44, Simon Marlow wrote:
>> I now think '\' is too quiet to introduce a new layout context. The
>> need is really for a combination of '\' and 'case', that is
>> single-argument so
>> that we don't have to write parentheses. I think '\case' does the job
>> perfectly. If you want a multi-clause multi-argument function, then give
>> it a
> There is an advantage here for "\of" in favor of "\case", namely that "of"
> already introduces layout, while "case" does not.
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