On 29/01/2016 10:56 AM, Uwe Ligges wrote:
On 29.01.2016 15:21, Berry Boessenkool wrote:
>
> Hi,
> in our Berlin R User Group meeting yesterday we talked about dependencies in
package development.
> One thing that came up is that it's a good practice to explicitly write
package::function in the code.
>
> Is it worth to go through all of my package and enhance the code in all
instances?
No, *if* you import anyway (see below).
> Or do you think that NAMESPACE sufficiently prevents using a function with
the same name from another package than intended and people reading source code
should be aware of that anyways?
Yes.
I'd add one caveat here: if you explicitly import things by name, this
is definitely true.
If you import everything from another package, then conceivably you
could end up with problems: e.g. you import all of package A and all of
package B. You want Fn from B, and since A doesn't have a function like
that, you're fine. But later if package A adds a function called Fn,
you might get in trouble and end up using the wrong one.
So use
importFrom(A, something)
importFrom(B, Fn)
rather than
import(A, B)
Duncan Murdoch
> If Answer1==YES:
> Should I also refer to other functions within my own package through
myPackage::otherFunction?
Yes, *if* you only suggest the package and do not import from the
namespace unconditionally, you should do that.
I think Berry was referring to the case where package Foo has function
Fn, and was asking whether he should use Foo::Fn within the code of
package Foo. The answer to that is no. Your own locally defined
functions generally have precedence over ones from other packages
(unless you mess around with environments; don't do that).
__
R-package-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-package-devel
