I have vague recollections of seeing this question discussed on r-help
previously, but I can't find the relevant postings.
I want to determine (from within a given function) the name of the
function
calling that given function.
E.g. if I have a function foo() which calls a function bar(), and also
a function clyde() which calls bar(), I want to have, in the code of
bar(),
an instruction which will return the character string "foo" if bar()
was
called from foo() and the string "clyde" if bar() was called from
clyde().
Without really understanding what I'm doing I cobbled together the
following:
fname <- as.character(sys.call(-1))[1]
This ***seems*** to work, at least in simple test cases.
But is it reliably robust? Are there traps for young players that I am
not seeing?
My ``solution'' returns NA as the value of fname if bar() is called
from the
command line, rather than being called by foo() or clyde(). This is
acceptable.
I think ....
Any avuncular advice from those younger and wiser than myself? :-)
cheers,
Rolf Turner
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Not sure if this is important to you but R functions don't have to have names so what you get back won't be a name if the function was anonymous. In the example below an anonymous function calls fname and the returned string is the calling sequence but that's not its name since it has no name. In fact, in a sense no R functions have names. You can store them in variables and call that variable its "name" but that is not an intrinsic part of the function itself. A function is just an environment, an argument list and a body -- no name.> fname <- function() as.character(sys.call(-1))[1] > (function() fname())()[1] "(function() fname())" On Sun, Sep 27, 2009 at 7:24 PM, Rolf Turner <r.turner at auckland.ac.nz> wrote:> > I have vague recollections of seeing this question discussed on r-help > previously, but I can't find the relevant postings. > > I want to determine (from within a given function) the name of the function > calling that given function. > > E.g. if I have a function foo() which calls a function bar(), and also > a function clyde() which calls bar(), I want to have, in the code of bar(), > an instruction which will return the character string "foo" if bar() was > called from foo() and the string "clyde" if bar() was called from clyde(). > > Without really understanding what I'm doing I cobbled together the > following: > > fname <- as.character(sys.call(-1))[1] > > This ***seems*** to work, at least in simple test cases. > > But is it reliably robust? ?Are there traps for young players that I am > not seeing? > > My ``solution'' returns NA as the value of fname if bar() is called from the > command line, rather than being called by foo() or clyde(). ?This is > acceptable. > I think .... > > Any avuncular advice from those younger and wiser than myself? :-) > > ? ? ? ?cheers, > > ? ? ? ? ? ? ? ?Rolf Turner > > ###################################################################### > Attention:\ This e-mail message is privileged and confid...{{dropped:9}} > > ______________________________________________ > R-help at 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. >
Not answering your question, but just pointing out the example of base::.NotYetImplemented() essentially doing the same thing. Best, baptiste 2009/9/28 Rolf Turner <r.turner at auckland.ac.nz>:> > I have vague recollections of seeing this question discussed on r-help > previously, but I can't find the relevant postings. > > I want to determine (from within a given function) the name of the function > calling that given function. > > E.g. if I have a function foo() which calls a function bar(), and also > a function clyde() which calls bar(), I want to have, in the code of bar(), > an instruction which will return the character string "foo" if bar() was > called from foo() and the string "clyde" if bar() was called from clyde(). > > Without really understanding what I'm doing I cobbled together the > following: > > fname <- as.character(sys.call(-1))[1] > > This ***seems*** to work, at least in simple test cases. > > But is it reliably robust? ?Are there traps for young players that I am > not seeing? > > My ``solution'' returns NA as the value of fname if bar() is called from the > command line, rather than being called by foo() or clyde(). ?This is > acceptable. > I think .... > > Any avuncular advice from those younger and wiser than myself? :-) > > ? ? ? ?cheers, > > ? ? ? ? ? ? ? ?Rolf Turner > > ###################################################################### > Attention:\ This e-mail message is privileged and confid...{{dropped:9}} > > ______________________________________________ > R-help at 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. >