On 21/04/2012 03:18 PM, clipka wrote:

> All I understand is bollocks, but something tells me the concept
> is probably so trivial that a handful of well-chosen words could explain
> it all

When I write Haskell code "in a monad", the compiler is automatically 
inserting a bunch of invisible function calls to the "bind function" of 
the monad in question.

The bind function gets given two arguments: The result from the previous 
statement, and a function representing /all/ of the following 
statements. So it gets to decide if and how the rest of the code block 
executes.

In short, between every pair of statements, a bunch of user-defined code 
is invisibly being executed, allowing it to do totally hoopy things to 
how your code runs.

And that's basically /it/.

(Now wasn't that such an anti-climax? Everybody makes such a Big Deal 
out of monads, that sometimes when a person finally understands what 
they are, it doesn't seem all that impressive, so they go away thinking 
they missed something...)

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