
112 R Programming for Bioinformatics
to step into the method that is dispatched to.
Instead, the function trace can be used to debug S4 methods. This function
is discussed in more detail in Section 9.3.5 and so here we will simply give
the syntax for debugging a particular method. In the code below, the first
command shows how to begin debugging on entry into the dim method with
signature eSet. The second command also places a call to browser on exit
from the method.
trace("dim", browser, signature = c("eSet"))
trace("dim", browser, exit=browser, signature = c("eSet"))
untrace("dim", signature = c("eSet"))
3.8 Managing S3 and S4 together
Perhaps one of