[ccan] bitmap/tal again

[Rusty Russell]

David Gibson <david at gibson.dropbear.id.au> writes:
> On Fri, Sep 15, 2017 at 01:03:55AM -0700, Ian Zimmerman wrote:
>> Hi, so I'd like to add the bitmap/tal submodule as discussed here:
>> 
>> https://github.com/rustyrussell/ccan/pull/60
>> 
>> but I'm not familiar enough with ccan dependency declarations yet :(
>> 
>> 1. Should the dependency on tal be declared in bitmap/_info or in
>> bitmap/tal/_info?  The latter seems more natural, but for some reason
>> the final pull request on github shows the former.  I don't know if
>> that's something I did and Rusty didn't correct, or something that Rusty
>> did.  (I also don't quite understand github, ARGH!)
>
> In bitmap/tal/_info, definitely.  Putting it in bitmap/_info will
> change the dependencies of the base bitmap module, not your new
> submodule.
>
>> 2. Does bitmap/tal need to declare dependency on bitmap, or is that
>> automatic?  Or maybe the other way?  I tried to look at other submodules
>> in the tree, but there are only a few and none that quite match the
>> relationship between this proposed pair.
>
> Looking at ccan/tal/str, looks like the surrounding module should be
> explicitly listed in dependencies.

Indeed.  There's no implied dependency between a submodule and parent
module.  Generally the submodule will depend on the parent module, but
we can also imagine a foo module which depends on a foo/lowlevel module.

Cheers,
Rusty.