[Ocaml-lib-devel] More additions to Enum API

[Brian H. <bh...@sp...>]

It's a cold, rainy, sunday afternoon and I'm bored- so I added the
following functions to the Enum API: iter2, iter2i, foldi, fold2, fold2i,
map2, map2i.

The *i functions pass an index counter which counts from 0 to n through 
the enumeration.  The 2 functions take two enumerations.  Note that I'm 
not doing a lot of checking at the moment to make sure the two 
enumerations are the same length.  The iterations stop when one interation 
runs out of elements.  I took a swipe at adding pedantic checking- while 
it's possible, it's not pretty.  Although most of the unprettiness came 
from handling unknown-length enumerations (this might be an argument 
against them)- I am more inclined that pedantic assertions that the two 
enumerations be the same length simply isn't that important.

Brian