Re: [Haskell-cafe] let vs. where

On Tue, 2007-11-13 at 13:51 -0800, 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

where 'a' clearly isn't a function. Seems like a nice readable format to use. Probably everyone except me already knew this already though.

Yep. Haskell and Haskell code very often avoids special/corner cases. There's no reason that shouldn't work so it does. Other examples are: nullary fundeps, class Foo a | -> a where ... ; non/record syntax for pattern matching, case x of App {} -> ... ; guards pretty much everywhere