Re: [R-pkg-devel] import 'as' from another package

[Sebastian Meyer]

Following WRE 1.5.6 (Namespaces with S4 classes and methods), you should
have "Depends: methods" in your DESCRIPTION, and "import(methods)" or a
more selective "importFrom(methods, ...)" directive in your NAMESPACE.

Then you would usually use the NAMESPACE directive

importMethodsFrom(package, generic)

to explicitly import S4 methods exported from another package.
However, the raster package does not do

exportMethods(coerce)

so if you try

importMethodsFrom(raster, coerce)

you will get

> Error: object ‘coerce’ is not exported by 'namespace:raster'

when trying to install your package (also during R CMD check, of course).

To solve this problem, you could either

- import raster's entire NAMESPACE via import(raster)

- or ask maintainer("raster") to exportMethods(coerce)

- or do

importClassesFrom(raster, RasterLayer)

which will magically make the corresponding coerce methods available as
well.

HTH!

Sebastian Meyer


Am 21.07.20 um 00:41 schrieb Tim Keitt:
> Thanks for pointing to the bug.
> 
> Now I am finding I cannot use the 'as' definitions from 'raster' without
> loading the package. Do I need an @import directive that specifies the
> definitions in the 'raster' package? My understanding is that the
> 'setAs' function generates a 'coerce,...' signature but I'm not sure how
> to import it to my package.
> 
> Thanks again.
> 
> THK
> 
> On Mon, Jul 20, 2020 at 2:25 PM Sebastian Meyer  > wrote:
> 
> Yes, indeed, it is confusing. You don't need to file a new bug
> report, though. There is one already:
> 
> https://bugs.r-project.org/bugzilla/show_bug.cgi?id=17179
> 
> Please feel free to comment there. This thread could serve as
> another confirmation. :-)
> 
> Best regards,
> Sebastian
> 
> Am 20. Juli 2020 18:36:21 MESZ schrieb Ben Bolker  >:
> >    I think this is a classic confusing R message.  Try adding methods
> >to the Imports: statement in your DESCRIPTION file and see if that
> >helps. (Maybe I should file a bug report about that error message - it
> >confuses me every time.)
> >
> >On 7/20/20 12:34 PM, Tim Keitt wrote:
> >> It works but "check" gives
> >>
> >> > checking package dependencies ... ERROR
> >>   Namespace dependency not required: ‘methods’
> >>
> >> THK
> >>
> >> On Mon, Jul 20, 2020 at 11:24 AM Ben Bolker  
> >> >> wrote:
> >>
> >>     @importFrom methods as
> >>
> >>     ?
> >>
> >>     On 7/20/20 12:06 PM, Tim Keitt wrote:
> >>     > I have
> >>     >
> >>     >    if (!inherits(x, "RasterLayer")) x <- as(x, "RasterLayer")
> >>     >
> >>     > in a package and its not finding the coerce definition from the
> >>     raster
> >>     > package. I know I need to add an @import roxygen2 directive of
> >>     some kind,
> >>     > but I'm not sure the correct syntax. My first try generated a
> >>     warning that
> >>     > it was not needed.
> >>     >
> >>     > What is the correct way to do this? Or does raster need to
> >>     export this
> >>     > definition?
> >>     >
> >>     > THK
> >>     >
> >>     >       [[alternative HTML version deleted]]
> >>     >
> >>     > __
> >>     > R-package-devel@r-project.org
> 
> >>      > mailing list
> >>     > https://stat.ethz.ch/mailman/listinfo/r-package-devel
> >>
> >>     __
> >>     R-package-devel@r-project.org
> 
> >>      > mailing list
> >>     https://stat.ethz.ch/mailman/listinfo/r-package-devel
> >>
> >
> >       [[alternative HTML version deleted]]
> >
> >__
> >R-package-devel@r-project.org
>  mailing list
> >https://stat.ethz.ch/mailman/listinfo/r-package-devel
>

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Re: [R-pkg-devel] import 'as' from another package

[Tim Keitt]

Thanks for pointing to the bug.

Now I am finding I cannot use the 'as' definitions from 'raster' without
loading the package. Do I need an @import directive that specifies the
definitions in the 'raster' package? My understanding is that the 'setAs'
function generates a 'coerce,...' signature but I'm not sure how to import
it to my package.

Thanks again.

THK

On Mon, Jul 20, 2020 at 2:25 PM Sebastian Meyer  wrote:

> Yes, indeed, it is confusing. You don't need to file a new bug report,
> though. There is one already:
>
> https://bugs.r-project.org/bugzilla/show_bug.cgi?id=17179
>
> Please feel free to comment there. This thread could serve as another
> confirmation. :-)
>
> Best regards,
> Sebastian
>
> Am 20. Juli 2020 18:36:21 MESZ schrieb Ben Bolker :
> >I think this is a classic confusing R message.  Try adding methods
> >to the Imports: statement in your DESCRIPTION file and see if that
> >helps. (Maybe I should file a bug report about that error message - it
> >confuses me every time.)
> >
> >On 7/20/20 12:34 PM, Tim Keitt wrote:
> >> It works but "check" gives
> >>
> >> > checking package dependencies ... ERROR
> >>   Namespace dependency not required: ‘methods’
> >>
> >> THK
> >>
> >> On Mon, Jul 20, 2020 at 11:24 AM Ben Bolker  >> > wrote:
> >>
> >> @importFrom methods as
> >>
> >> ?
> >>
> >> On 7/20/20 12:06 PM, Tim Keitt wrote:
> >> > I have
> >> >
> >> >if (!inherits(x, "RasterLayer")) x <- as(x, "RasterLayer")
> >> >
> >> > in a package and its not finding the coerce definition from the
> >> raster
> >> > package. I know I need to add an @import roxygen2 directive of
> >> some kind,
> >> > but I'm not sure the correct syntax. My first try generated a
> >> warning that
> >> > it was not needed.
> >> >
> >> > What is the correct way to do this? Or does raster need to
> >> export this
> >> > definition?
> >> >
> >> > THK
> >> >
> >> >   [[alternative HTML version deleted]]
> >> >
> >> > __
> >> > R-package-devel@r-project.org
> >>  mailing list
> >> > https://stat.ethz.ch/mailman/listinfo/r-package-devel
> >>
> >> __
> >> R-package-devel@r-project.org
> >>  mailing list
> >> https://stat.ethz.ch/mailman/listinfo/r-package-devel
> >>
> >
> >   [[alternative HTML version deleted]]
> >
> >__
> >R-package-devel@r-project.org mailing list
> >https://stat.ethz.ch/mailman/listinfo/r-package-devel
>

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Re: [R-pkg-devel] import 'as' from another package

[Sebastian Meyer]

Yes, indeed, it is confusing. You don't need to file a new bug report, though. 
There is one already:

https://bugs.r-project.org/bugzilla/show_bug.cgi?id=17179

Please feel free to comment there. This thread could serve as another 
confirmation. :-)

Best regards,
Sebastian

Am 20. Juli 2020 18:36:21 MESZ schrieb Ben Bolker :
>    I think this is a classic confusing R message.  Try adding methods 
>to the Imports: statement in your DESCRIPTION file and see if that 
>helps. (Maybe I should file a bug report about that error message - it 
>confuses me every time.)
>
>On 7/20/20 12:34 PM, Tim Keitt wrote:
>> It works but "check" gives
>>
>> > checking package dependencies ... ERROR
>>   Namespace dependency not required: ‘methods’
>>
>> THK
>>
>> On Mon, Jul 20, 2020 at 11:24 AM Ben Bolker > > wrote:
>>
>> @importFrom methods as
>>
>> ?
>>
>> On 7/20/20 12:06 PM, Tim Keitt wrote:
>> > I have
>> >
>> >    if (!inherits(x, "RasterLayer")) x <- as(x, "RasterLayer")
>> >
>> > in a package and its not finding the coerce definition from the
>> raster
>> > package. I know I need to add an @import roxygen2 directive of
>> some kind,
>> > but I'm not sure the correct syntax. My first try generated a
>> warning that
>> > it was not needed.
>> >
>> > What is the correct way to do this? Or does raster need to
>> export this
>> > definition?
>> >
>> > THK
>> >
>> >       [[alternative HTML version deleted]]
>> >
>> > __
>> > R-package-devel@r-project.org
>>  mailing list
>> > https://stat.ethz.ch/mailman/listinfo/r-package-devel
>>
>> __
>> R-package-devel@r-project.org
>>  mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-package-devel
>>
>
>   [[alternative HTML version deleted]]
>
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Re: [R-pkg-devel] import 'as' from another package

[Tim Keitt]

That did it. Thanks Ben.

THK

On Mon, Jul 20, 2020 at 11:36 AM Ben Bolker  wrote:

>I think this is a classic confusing R message.  Try adding methods to
> the Imports: statement in your DESCRIPTION file and see if that helps.
> (Maybe I should file a bug report about that error message - it confuses me
> every time.)
> On 7/20/20 12:34 PM, Tim Keitt wrote:
>
> It works but "check" gives
>
> > checking package dependencies ... ERROR
>   Namespace dependency not required: ‘methods’
>
> THK
>
> On Mon, Jul 20, 2020 at 11:24 AM Ben Bolker  wrote:
>
>> @importFrom methods as
>>
>> ?
>>
>> On 7/20/20 12:06 PM, Tim Keitt wrote:
>> > I have
>> >
>> >if (!inherits(x, "RasterLayer")) x <- as(x, "RasterLayer")
>> >
>> > in a package and its not finding the coerce definition from the raster
>> > package. I know I need to add an @import roxygen2 directive of some
>> kind,
>> > but I'm not sure the correct syntax. My first try generated a warning
>> that
>> > it was not needed.
>> >
>> > What is the correct way to do this? Or does raster need to export this
>> > definition?
>> >
>> > THK
>> >
>> >   [[alternative HTML version deleted]]
>> >
>> > __
>> > R-package-devel@r-project.org mailing list
>> > https://stat.ethz.ch/mailman/listinfo/r-package-devel
>>
>> __
>> R-package-devel@r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-package-devel
>>
>

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Re: [R-pkg-devel] import 'as' from another package

[Ben Bolker]

    I think this is a classic confusing R message.  Try adding methods 
to the Imports: statement in your DESCRIPTION file and see if that 
helps. (Maybe I should file a bug report about that error message - it 
confuses me every time.)

On 7/20/20 12:34 PM, Tim Keitt wrote:
> It works but "check" gives
>
> > checking package dependencies ... ERROR
>   Namespace dependency not required: ‘methods’
>
> THK
>
> On Mon, Jul 20, 2020 at 11:24 AM Ben Bolker  > wrote:
>
> @importFrom methods as
>
> ?
>
> On 7/20/20 12:06 PM, Tim Keitt wrote:
> > I have
> >
> >    if (!inherits(x, "RasterLayer")) x <- as(x, "RasterLayer")
> >
> > in a package and its not finding the coerce definition from the
> raster
> > package. I know I need to add an @import roxygen2 directive of
> some kind,
> > but I'm not sure the correct syntax. My first try generated a
> warning that
> > it was not needed.
> >
> > What is the correct way to do this? Or does raster need to
> export this
> > definition?
> >
> > THK
> >
> >       [[alternative HTML version deleted]]
> >
> > __
> > R-package-devel@r-project.org
>  mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-package-devel
>
> __
> R-package-devel@r-project.org
>  mailing list
> https://stat.ethz.ch/mailman/listinfo/r-package-devel
>

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Re: [R-pkg-devel] import 'as' from another package

[Tim Keitt]

It works but "check" gives

> checking package dependencies ... ERROR
  Namespace dependency not required: ‘methods’

THK

On Mon, Jul 20, 2020 at 11:24 AM Ben Bolker  wrote:

> @importFrom methods as
>
> ?
>
> On 7/20/20 12:06 PM, Tim Keitt wrote:
> > I have
> >
> >if (!inherits(x, "RasterLayer")) x <- as(x, "RasterLayer")
> >
> > in a package and its not finding the coerce definition from the raster
> > package. I know I need to add an @import roxygen2 directive of some kind,
> > but I'm not sure the correct syntax. My first try generated a warning
> that
> > it was not needed.
> >
> > What is the correct way to do this? Or does raster need to export this
> > definition?
> >
> > THK
> >
> >   [[alternative HTML version deleted]]
> >
> > __
> > R-package-devel@r-project.org mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-package-devel
>
> __
> R-package-devel@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-package-devel
>

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Re: [R-pkg-devel] import 'as' from another package

[Ben Bolker]

   @importFrom methods as

?

On 7/20/20 12:06 PM, Tim Keitt wrote:

I have

   if (!inherits(x, "RasterLayer")) x <- as(x, "RasterLayer")

in a package and its not finding the coerce definition from the raster
package. I know I need to add an @import roxygen2 directive of some kind,
but I'm not sure the correct syntax. My first try generated a warning that
it was not needed.

What is the correct way to do this? Or does raster need to export this
definition?

THK

[[alternative HTML version deleted]]

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[R-pkg-devel] import 'as' from another package

[Tim Keitt]

I have

  if (!inherits(x, "RasterLayer")) x <- as(x, "RasterLayer")

in a package and its not finding the coerce definition from the raster
package. I know I need to add an @import roxygen2 directive of some kind,
but I'm not sure the correct syntax. My first try generated a warning that
it was not needed.

What is the correct way to do this? Or does raster need to export this
definition?

THK

[[alternative HTML version deleted]]

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