[m-rev.] for review: Move some code to new io.error_util module.

[Zoltan Somogyi]

2023-01-13 17:08 GMT+11:00 "Peter Wang" <novalazy at gmail.com>:
> This reduces the size of io.m a bit.

That's good.

> The other reason for moving the
> code is to allow modules that occur in a dependency cycle with io.m
> to read results from io.error_util.trans_opt, whereas they may have
> been prevented from reading io.trans_opt.

Have you verified whether that is the case? I think the diff is worthwhile
whatever the answer is; I am just curious.

> library/io.m:
> library/io.error_util.m:
>     Move is_error, throw_on_error and other similar predicates to a
>     new undocumented submodule of io.m.
> 
>     Also move the support functions/predicates used by those predicates.
> 
>     Add forwarding predicates for the predicates that are part of the
>     io.m public interface.

The diff contains no such forwarding predicates, since they are not needed.

I have not looked at the moved code in detail, since I presume that you did not modify it.
If that's so, then the diff is fine.

Zoltan.