Re: [Haskell-cafe] let vs. where

On Thu, 15 Nov 2007 12:31:07 +0100, Henning Thielemann wrote:

On Tue, 13 Nov 2007, Dan Piponi wrote:

...

On Nov 13, 2007 1:24 PM, Ryan Ingram wrote:

...

I tend to prefer where, but I think that guards & function declarations are more readable than giant if-thens and case constructs.

Up until yesterday I had presumed that guards only applied to functions. But I was poking about in the Random module and discovered that you can write things like

a | x > 1 = 1 | x < -1 = -1 | otherwise = x

Btw. I would write here min 1 (max (-1) x) or even better define a function for such clipping, since it is needed quite often.

The value of 'a' needs only be calculated once; when defined at top level, 'a' is a CAF; in a 'where' clause, the value is also calculated once. -- Met vriendelijke groet, Henk-Jan van Tuyl -- http://functor.bamikanarie.com http://Van.Tuyl.eu/ --