This message could be useful for people fairly new to S4 classes.
Therefore r-help and not r-devel.
One use for showMethods(), important to me,
is to find all methods that use a particular class in their signatures.
This works:
showMethods(class="Action", where="package:CTDesignExplorer")
It finds the methods in the package.
This works:
showMethods(class="Action", where=topenv(parent.frame()))
in the sense that it finds nothing (looking in .GlobalEnv).
"no applicable functions"
The default for "where" is where=topenv(parent.frame()),
so you'd think this would also give nothing.
showMethods(class="Action")
Instead, it prints names of hundreds of S4 generics, reporting that they are
not.
For example,
Function "xvcopy":
<not an S4 generic function>
that come from packages installed even though they are not loaded.
Since this was the first thing I tried,
getting to the bottom of it derailed me for hours.
The problem seems to be from this, in the definition of showMethod:
if (length(f) == 0L) {
f <- if (missing(.where)) ### This is the problem. It's missing,
even though the default value is set.
getGenerics()
else getGenerics(.where)
}
I think better would be just
f <- getGenerics(.where)
Then the default value would apply.
This would forestall a vast downpour of reports about generics claiming that
they are not generics.
Or maybe someone can explain the thinking behind the if clause.
Thanks.
-Roger Day
> sessionInfo()
R version 3.0.1 (2013-05-16)
Platform: x86_64-apple-darwin10.8.0 (64-bit)
locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8
attached base packages:
[1] stats graphics grDevices utils datasets methods base
other attached packages:
[1] CTDesignExplorer_1.3.9
loaded via a namespace (and not attached):
[1] BiocGenerics_0.6.0 Biostrings_2.28.0 grid_3.0.1 IRanges_1.18.1
[5] lattice_0.20-15 parallel_3.0.1 stats4_3.0.1 tools_3.0.1
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
