Eric E Moore <[EMAIL PROTECTED]> writes: > "Eric G. Miller" <[EMAIL PROTECTED]> writes: >> In C, statements are executed in order. I'm not too up on >> functional languages, but I seem to recall they need special syntax >> to execute statements sequentially. > > Not really. top level forms in a scheme program are executed > sequentially, and there's a number of forms that execute their > statements sequentially. I'm not up on haskell, or other "pure" > functional languages though :)
Right, in Scheme it's easy enough to do (begin (foo) (bar) (baz)) to cause things to be executed in order. Haskell doesn't have such a construct intrinsically. But what it does have is a concept called a monad, which allows you to attach state to execution. Probably the most common monad is "IO", which reflects the state of input/output operations (like printing to the display). The 'do' keyword then executes statements in order within a monad (doing ugly magic with lambdas, I think). I've found that monads are kind of hard to wrap your head around. I wrote some monad code once upon a time but don't really remember how it works; what it's supposed to do is pretty obvious. :-) (In particular, http://web.mit.edu/dmaze/Public/hdc/ has source code for a non-optimizing compiler for a simple Java-like language to MIPS in Haskell. Because you all care, I'm sure, and because it seemed like more fun than my thesis at the time. :-) -- David Maze [EMAIL PROTECTED] http://people.debian.org/~dmaze/ "Theoretical politics is interesting. Politicking should be illegal." -- Abra Mitchell -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
