[Haskell-cafe] Comments from OCaml Hacker Brian Hurt

[Duncan Coutts]

On Thu, 2009-01-15 at 19:46 +0000, Andrew Coppin wrote:

> PS. As a small aside... Is the Monoid class actually used *anywhere* in 
> all of Haskell?

Yes.

They're used quite a lot in Cabal. Package databases are monoids.
Configuration files are monoids. Command line flags and sets of command
line flags are monoids. Package build information is a monoid.

It is also used in the Foldable class which is a nice interface for
traversing/visiting structures. Binary serialisation is also a monoid.

Duncan