Bang patterns

Simon Marlow marlowsd at
Fri Feb 8 13:27:41 CET 2013

On 08/02/13 11:49, Ben Millwood wrote:
> On Thu, Feb 07, 2013 at 12:24:48PM +0000, Simon Marlow wrote:
>> FWIW, I really dislike whitespace-significant syntax.  f ! x should
>> mean the same as f !x.  Look at the trouble we have with qualified
>> operators: how many people have tried to write [Monday..] and been
>> surprised that it doesn't work?
> What about `elem`? I don't think anyone would argue that ` elem ` makes
> sense.

Prelude> 1 ` elem ` [1..10]
Prelude> 1 ` {- comment -} elem ` [1..10]

backticks are part of the context-free syntax, not the lexical syntax 
(as they should be!).  I'm of the opinion that the lexical syntax should 
be as simple, and as far as possible everything should be pushed into 
the context-free syntax.


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