[m-dev.] for review: last call modulo constructors [1/3]

[Fergus Henderson]

On 22-Jun-1998, David Matthew Overton <dmo at students.cs.mu.oz.au> wrote:
> compiler/export.m:
> 	Add `ref_in' and `ref_out' arg_modes to switches in
> 	`get_input_args' and `copy_output_args'.  But don't produce
> 	any code for them yet. (XXXs have been added in appropriate
> 	places).

I think it would be better to add calls to

	error("Sorry, not yet implemented: ...")

as well as the XXXs.

> compiler/modecheck_unify.m:
> 	Add support for `free(alias)' insts.
> 	Disallow scheduling of constructions of partially instantiated
> 	data structures until we come up with a better algorithm for
> 	when this should be done and when it shouldn't.  At the
> 	moment, partially instantiated data structures are only
> 	created by LCO, which is called after mode checking.

Could you explain the rationale for this change in a bit more detail?
What would be wrong with say scheduling such constructions at the
earliest point possible?

-- 
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"
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