[Haskell-cafe] Is 'flip' really necessary?

[Ivan Miljenovic]

On 26 July 2010 16:33, David Virebayre <dav.vire+haskell at gmail.com> wrote:
> On Sun, Jul 25, 2010 at 11:53 PM, Edward Z. Yang <ezyang at mit.edu> wrote:
>
>> An interesting alternate spin on flip is infix notation combined with partial
>> application, such as:
>>
>>    (`foobar` 3)
>>
>> which is equivalent to
>>
>>    \x -> foobar x 3
>>
>> I frequently use this, although the jury's out on whether or not it's more readable.
>
> I had HLint suggest me this :
>
> before :
>
> listeEtagTot = concatMap (flip listeEtagArm cfgTypesTringle) listeArmOrd
>
> after :
>
> listeEtagTot = concatMap (`listeEtagArm` cfgTypesTringle) listeArmOrd

However, if you had something like this, I think the flip version is nicer:

With flip:

foo = map (f . flip g x)

Without flip:

foo = map (f . (`g` x))

-- 
Ivan Lazar Miljenovic
Ivan.Miljenovic at gmail.com
IvanMiljenovic.wordpress.com