Re: top-repl priority of guile module

[Ludovic Courtès]

Hi,

Neil Jerram <address@hidden> writes:

> It seems to me, though, that this is all a matter of ordering, not of
> whether the duplicates processing gets invoked.  I don't know all the
> details of the duplicate processing, but by default I would expect a
> later use-modules (or similar operation) to override an earlier one.
> Is that what happens?

Roughly, yes.  However, the semantics of `module-use!' are very
different from those of `use-modules' (unlike what one might think ;-)).
While `use-modules' honors the duplicate binding policies, including
`replace' as Kevin noted, `module-use!' does no such thing: it blindly
overrides bindings.  A more important concern is that the order of
`module-use!' invocations matters, which leads to all these strange side
effects.

`module-use!' is a low-level primitive that really should not be used by
the "normal user" IMO.  Instead, one should rather use
`module-use-interfaces!' which has the same semantics as `use-modules'.

Getting back to the problem at hand: Since we want to emulate the
behavior of `use-modules', the safest way would be to use
`module-use-interfaces!', although we can certainly find (fragile?)
workarounds.

Thanks,
Ludovic.