Re: [Haskell-cafe] Is there a null statement that does nothing?

Hi Curt, Thanks for the tips. Looks like return () would be a good candidate for that null statement I was seeking earlier. Michael --- On Sun, 10/25/09, Curt Sampson wrote: From: Curt Sampson Subject: Re: [Haskell-cafe] Is there a null statement that does nothing? To: "michael rice" Cc: "haskell-cafe@haskell.org" Date: Sunday, October 25, 2009, 12:08 AM On 2009-10-21 18:27 -0700 (Wed), michael rice wrote:

Those nested IF/THEN/ELSEs are real killers. I kind of use them to sort out my thoughts, then end up with a nested mess. The restructuring to WHENs went smoothly and looks a lot cleaner besides.

Indeed. Monadic control flow is one of the basic keys to being able to write nice code in Haskell; it's the moral equivalant of using polymorphism rather than than "case" or "switch" in OO languages. (Well, some would disagree, but that gets into the whole OO vs. functional debate.) You'll probably want to spend some time with one of the zillion monad tutorials at some point (I like "All About Monads") to learn more about these things. BTW, look up the source code for "when". :-)   http://haskell.org/ghc/docs/latest/html/libraries/base/src/Control-Monad.htm... cjs -- Curt Sampson               +81 90 7737 2974            Functional programming in all senses of the word:                    http://www.starling-software.com