On 10/07/2012 07:33, Mikhail Vorozhtsov wrote:
On 07/10/2012 01:09 AM, Bardur Arantsson wrote:
On 07/09/2012 06:01 PM, Mikhail Vorozhtsov wrote:
On 07/09/2012 09:52 PM, Twan van Laarhoven wrote:
On 09/07/12 14:44, Simon Marlow wrote:
I now think '\' is too quiet to introduce a new layout context. The pressing 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 name.
There is an advantage here for "\of" in favor of "\case", namely that "of" already introduces layout, while "case" does not. Do you think that adding "\" + "case" as a layout herald would complicate the language spec and/or confuse users? Because it certainly does not complicate the implementation (there is a patch for \case already).
Just being anal here, but: The existence of a patch to implement X does not mean that X doesn't complicate the implemenatation. In general, yes. But that particular patch[1] uses ~20 lines of pretty straightforward (if I'm allowed to say that about the code I wrote myself) code to handle layout. Which in my book is not complex at all.
[1] http://hackage.haskell.org/trac/ghc/attachment/ticket/4359/one-arg-lambda-ca...
The need to keep track of the previous token in the lexer *is* ugly though. Cheers, Simon