[R] Extracting the name of a function (inverse of match.fun("myFun"))

[Eloi Mercier]

On 12-08-29 04:00 PM, Peter Langfelder wrote:
> On Wed, Aug 29, 2012 at 3:36 PM, Peter Langfelder
> <peter.langfelder at gmail.com> wrote:
>> Hi all,
>>
>> is there a way to extract the name of a function, i.e. do the reverse
>> of match.fun applied to a character string? I would like to print out
>> the name of a function supplied to another function as an argument.
>>
>> For example:
>>
>> myFunc = function(x) { x+1 }
>>
>> applyFunc = function(fnc, x)
>> {
>>    fnc = match.fun(fnc)
>>    fnc(x)
>> }
>>
>> Is there a way to obtain "myFunc" from the argument fnc in applyFnc
>> the following call is issued?
>>
>> applyFnc(myFunc, 1)
> ...or am I missing the basic fact that since arguments to functions in
> R are passed by copy, the name is lost/meaningless?
You can pass the function name as a string.

applyFunc = function(fun, x)
{
   fnc = match.fun(fun)
    fnc(x)
    print(fun)
}

applyFunc("myFunc", 1)
[1] "myFunc"

PS : avoid renaming the name of your argument within the function ("fnc 
= match.fun(fnc)").

Cheers,

Eloi

>
> Thanks,
>
> Peter
>
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>


-- 
Eloi Mercier
Bioinformatics PhD Student, UBC
Paul Pavlidis Lab
2185 East Mall
University of British Columbia
Vancouver BC V6T1Z4