Benjamin Franksen wrote:
Brian Brunswick wrote:
One thing that I keep seeing people say (not you), is that
monads /sequence/ side effects. This is wrong, or at
least a limited picture.
/All/ of the above structures are about combining compatible things things
together in a row.
I
On 2007-08-14, Dan Piponi [EMAIL PROTECTED] wrote:
On 8/14/07, Sebastian Sylvan [EMAIL PROTECTED] wrote:
I like the very light weight analogy (which works for most practical
uses of monads) that a monadic action is a recipe
Many introductory programming books present the idea of a program as
Brian Brunswick wrote:
One thing that I keep seeing people say (not you), is that
monads /sequence/
side effects. This is wrong, or at
least a limited picture.
/All/ of the above structures are about combining compatible things things
together in a row.
/None/ of them force any particular
On Aug 13, 2007, at 16:29 , Benjamin Franksen wrote:
Let's take the simplest example: Maybe. The effect in question is the
premature abortion of a computation (when Nothing is returned). And of
course Maybe sequences these effects, that's what you use it for: the
_first_ action to be
On Mon, Aug 13, 2007 at 05:13:01PM -0400, Brandon S. Allbery KF8NH wrote:
On Aug 13, 2007, at 16:29 , Benjamin Franksen wrote:
Let's take the simplest example: Maybe. The effect in question is the
premature abortion of a computation (when Nothing is returned). And of
course Maybe sequences
David Roundy wrote:
It's the *effect* of a monad, not the *side* effect. The type of =
defines this dependency. And when you have a chain of dependencies, that
is sometimes referred to as a sequence. True, it's not mystical, but it's
still sequenced.
How can a Haskell type define a data
On 13/08/07, David Roundy [EMAIL PROTECTED] wrote:
Try executing:
do { x - return 2; undefined; return (x*x); }
in any monad you like, and you'll find that regardless of the *data*
dependencies (the return value of this monadic action is unambiguous), the
undefined is evaluated *before*
On Mon, 2007-08-13 at 22:29 +0200, Benjamin Franksen wrote:
Brian Brunswick wrote:
One thing that I keep seeing people say (not you), is that
monads /sequence/
side effects. This is wrong, or at
least a limited picture.
/All/ of the above structures are about combining compatible
On 8/13/07, David Roundy [EMAIL PROTECTED] wrote:
Try executing:
do { x - return 2; undefined; return (x*x); }
in any monad you like
instance Monad M where
return a = M a
~(M a) = f = f a
Or is that cheating?
--
Dan
___
Haskell-Cafe
On 8/13/07, David Roundy [EMAIL PROTECTED] wrote:
| Try executing:
|
| do { x - return 2; undefined; return (x*x); }
|
| in any monad you like
It's not just the identity monad:
Prelude :m +Control.Monad.State
Prelude Control.Monad.State flip evalState () $ do { x - return 2;
undefined;
10 matches
Mail list logo
