[mercury-users] Re: Mercury for Mac ?

[Fergus Henderson]

Peter Moulder, you wrote:
> On Fri, 7 Nov 1997, Fergus Henderson wrote:
> 
> > If you can get a vaguely Unix-like environment (i.e. gcc, make, sh, and a
> > few others) under MacOS, then it would not be too hard.
> 
> So far, Mercury has avoided gcc dependencies, hasn't it?  (Though I know 
> it does benefit from having gcc extensions present, in terms of efficiency.)
> 
> If one just wanted a bare-bones Mercury environment (no Mmake), wouldn't 
> any ANSI C environment suffice, so long as someone in a Unix environment 
> compiles the Mercury compiler to ANSI C output?

Yes.  But a bare-bones Mercury environment would be fairly bare.
Although the compiler itself needs only ANSI C, quite a bit of the
infrastructure basically assumes a Unix-like (or POSIX) environment.
To start with, we use an autoconf configuration script, so for a
non-Unix environment, you'd need to configure it by hand.
And `mmc', `ml', `mgnuc', `mercury_update_interface', etc. are all shell
scripts.  You'd need to reimplement those (they total about 1000 lines or so).
Also the Mercury compiler is itself built using Mmake, and although you
could build it by hand, that would be a bit of a hassle.
When all's said and done I think it would just be much less hassle
for greater benefit to use something like MachTen, at least for
building Mercury from the source code.  You could perhaps then create a
binary release for Mac which didn't need MachTen.

> I don't know whether the libraries assume POSIX, and I suppose that 
> filesystem access (esp. `/' vs. `:' vs. `\') would need changes.

The Mercury libraries mostly assume only ANSI C,
but there are some places in the runtime that make use of some POSIXisms.
I think mostly it is done with conditional compilation, so it shouldn't
be too hard, but it would probably require a bit of effort.

The pathname-dependent code is mostly in the shell scripts and the
compiler's Mmake files; as for `/' vs `:' vs `\', in the Mercury code
I think only one predicate in the library (dir__directory_separator/1)
should need changing.

-- 
Fergus Henderson <fjh at cs.mu.oz.au>   |  "I have always known that the pursuit
WWW: <http://www.cs.mu.oz.au/~fjh>   |  of excellence is a lethal habit"
PGP: finger fjh at 128.250.37.3         |     -- the last words of T. S. Garp.