[racket-dev] [racket] Feature request: multiple keys in sort

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Mon Jun 11 16:47:33 EDT 2012

I am still for a combinator to generate comparisons. I like this idea a lot. 

On Jun 11, 2012, at 4:46 PM, Eli Barzilay wrote:

> Just now, Matthias Felleisen wrote:
>> On Jun 11, 2012, at 3:31 PM, Eli Barzilay wrote:
>>> Just now, Robby Findler wrote:
>>>> I'd love to see something that at least handles the case of 2
>>>> levels of nesting (if we consider the current situation to be one
>>>> level of nesting), absolutely.
>>> OK.  (The difference between dealing with 2 levels and N levels is
>>> minor.)
>> But the example isn't about nesting at all. It is about
>> lexicographic comparisons with potentially distinct comparison
>> operations per key [path]. Am I misunderstanding something?
>> I am with Eli in that I don't think this is a common problem, and
>> that a mechanism for comparing comparison operators and keys sounds
>> like a promising way to deal with this problem.
> I think that Robby meant nesting of the comparisons in the composed
> comparison function.
> -- 
>          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
>                    http://barzilay.org/                   Maze is Life!

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