[Haskell-cafe] [Haskell] ANNOUNCE multiarg - parser combinators for command line parsing

[Omari Norman]

On Mon, Jan 30, 2012 at 03:19:47PM +0100, Henning Thielemann wrote:
> 
> On Sun, 29 Jan 2012, Simon Meier wrote:
> 
> >I'm currently using Neil Mitchell's cmdargs package [1]. How does your
> >package compare to that?
> 
> Last time I checked cmdargs it was not referential transparent. Is
> multiarg better in this respect?
> 

Absolutely, multiarg is 100% referentially transparent.

The main data type in multiarg is a monad transformer, so if the
programmer really wants to write something that does IO or is otherwise
not referentially transparent, then she can. Certainly there is no need
to do this though. I'd expect one would usually put the transformer on
top of Identity, as I have always done so far. But the option is there
if you want it. --Omari