R help - Apr 2007 - Referencing function name from within function

Hello,

For verbose coding I'd like to do something like:
> myfunction <- function(x){
>       if (a){
>               stop(paste(myfunction_name_here,"requires xyz!")
>       }       
Is that possible?

Thanks for any hints, Joh

I dunno much about such things, but a wee experiment seems to
indicate that the following structure does what you want:

        myfunction <- function(x){
                nm <- as.character(match.call())[1]
                a  <- TRUE
                if (a){
                        stop(paste(nm,"requires xyz!"))
                }       
        }

                                cheers,

                                        Rolf Turner
                                        rolf at math.unb.ca

===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+==Original
message:
> For verbose coding I'd like to do something like:
> > myfunction <- function(x){
> >       if (a){
> >               stop(paste(myfunction_name_here,"requires
xyz!")
> >       }       
> Is that possible?
        (Note:  In R *all* things are possible!)

Try this:
> myfunction <- function(){
+     # some calculations
+     # now get my name
+     .caller <- sys.call()
+     cat(paste(as.character(.caller[[length(.caller)]]),"needs
'xyz'\n"))
+ }
> myfunction()
myfunction needs 'xyz'
>
>


On 4/3/07, Johannes Graumann <johannes_graumann@web.de>
wrote:
>
> Hello,
>
> For verbose coding I'd like to do something like:
> > myfunction <- function(x){
> >       if (a){
> >               stop(paste(myfunction_name_here,"requires
xyz!")
> >       }
> Is that possible?
>
> Thanks for any hints, Joh
>
> ______________________________________________
> R-help@stat.math.ethz.ch 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.
>


-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem you are trying to solve?

	[[alternative HTML version deleted]]

Wott about this then?

myfunction <- function(x){
        temp <- sys.calls()[[1]]
        nm <- temp[length(temp)]
        a  <- TRUE
        if (a){
                stop(paste(nm,"requires xyz!"))
        }
}
> myfunction()
Error in myfunction() : myfunction requires xyz!
> lapply(1:10,myfunction)
Error in FUN(c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)[[1]], ...) : 
        myfunction requires xyz!

                                cheers,

                                        Rolf Turner
                                        rolf at math.unb.ca

===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+==Prof
Brian Ripley wrote:
> This presumes a function is always called by name.  Try
> 
> > lapply(1:10, myfunction)
> Error in FUN(c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)[[1]], ...) :
>          FUN requires xyz!
> 
> to see a (simple case of) the problem.
> 
> On Tue, 3 Apr 2007, rolf at math.unb.ca wrote:
> 
> > I dunno much about such things, but a wee experiment seems to
> > indicate that the following structure does what you want:
> >
> >        myfunction <- function(x){
> >                nm <- as.character(match.call())[1]
> >                a  <- TRUE
> >                if (a){
> >                        stop(paste(nm,"requires xyz!"))
> >                }
> >        }
> >
> >                                cheers,
> >
> >                                        Rolf Turner
> >                                        rolf at math.unb.ca
> >
> >
===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+==>
> Original message:
> >
> >> For verbose coding I'd like to do something like:
> >>> myfunction <- function(x){
> >>>       if (a){
> >>>               stop(paste(myfunction_name_here,"requires
xyz!")
> >>>       }
> >> Is that possible?
> >
> >        (Note:  In R *all* things are possible!)
> 
> I don't believe so.