I wrote: > > In the general case, if your language has both pure and impure > > functions, proving (at compile time) that something is not impure is an > > NP-complete problem.
On Mon, 16 Feb 2009, Mark Biggar wrote: > Worse it's equivalent to the halting problem (I.e., not solvable). Quite correct, my mistake. Please read as s/NP-complete/halting problem/g -Martin