[Chicken-users] How do I name these procedures?

[Jeronimo Pellegrini]

Hi,

I'm working on bindings for a library (MPFI, a C library for
interval arithmetic [0]), which I'd like to make available as
an egg.

Most mpfi functions receive pointer to structures that represent
intervals, and the return value is the first argument:

mpfi_add (a, b, c);  /* This is a <- b + c */

When translating this into Scheme, I thought I'd offer
three versions of each function. For example, the function
mpfi_add, which sums intervals, would generate:

(ia+ia!! a b c) ; same as mpfi (a, b, c)

(ia+ia! a b)    ; defined as (ia+ia!! a a c)
                ; a will be overwritten

(ia+ia a b)     ; allocates a new structure x and
                ; does (ia+ia!! x a b)
                ; See below:

(define (ia+ia a b)
  (let ((x (make-ia-interval)))
    (ia+ia!! x a b)
    x))

I am using the "ia" prefix/suffix to mean "interval arithmetic",
since there will also be functions like "ia+f64!"; also,
I may also in the future make bindings for affine arithmetic
libraries[1] -- which will then be named "aa+aa!", and so on.

I'd like some opinions on the naming of these procedures.
Since there are two mutating procedures for each C function,
I would use "!" in one of them and "!!" in another (and I
thought it'd be better to use "!!" on the one likely to be
the least used one). But I'm not really comfortable with
this ! and !! idea...

Any comments?

Thanks,
J.

[0] MPFI: http://cadadr.org/fm/package/mpfi.html
    (but right now the site seems to be down)

[1] Affine arithmetic:
http://en.wikipedia.org/wiki/Affine_arithmetic
http://www.ic.unicamp.br/~stolfi/EXPORT/projects/affine-arith/Welcome.html