[Haskell-cafe] let and fixed point operator

Andrew Coppin andrewcoppin at btinternet.com
Fri Aug 31 14:47:06 EDT 2007

Paul Hudak wrote:
> ok wrote:
>> What is so bad about
>>     f x = g x''
>>       where x'' = x' + transform
>>             x'  = x  * scale
>> (if you really hate inventing temporary names, that is).
> There's nothing at all wrong with this, assuming it's what you meant 
> to type :-), and it might even correspond perfectly to the 
> mathematical notation used in some textbook.  But I would argue that 
> this example is pretty simple, and that if there were a lot of xs and 
> x's and x''s then the chance of making a typing mistake is greater, I 
> believe, than if you had used x, xscaled, and xtransformed.  (On the 
> other hand this is all pretty subjective... :-)

OMG! "Mathematical" and "subjective" in the same sentence! ;-)

Personally, I find that if I've got more than 2 of the thing, I number 
them rather than attach multiple primes... but that's just me.

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