Re: [Rd] logical comparison of functions (PR#13588)
Duncan Murdoch wrote: > On 10/03/2009 4:35 PM, michael_ka...@earthlink.net wrote: >> Full_Name: Michael Aaron Karsh >> Version: 2.8.0 >> OS: Windows XP >> Submission from: (NULL) (164.67.71.215) >> >> >> When I try to say if (method==f), where f is a function, it says that >> the >> comparison is only possible for list and atomic types. I tried >> saying if >> (method!=f), and it gave the same error message. Would it be >> possible to repair >> it say that == and != comparisons would be possible for functions? > > This is not a bug. Please don't report things as bugs when they > aren't. "==" and "!=" are for atomic vectors, as documented. > > Use identical() for more general comparisons, as documented on the man > page for ==. note that in most programming languages comparing function objects is either not supported or returns false unless you compare a function object to itself. r is a notable exception: identical(function(a) a, function(a) a) # TRUE which would be false in all other languages i know; however, identical(function(a) a, function(b) b) # FALSE though they are surely identical functionally. btw. it's not necessarily intuitive that == works only for atomic vectors. vQ __ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Re: [Rd] logical comparison of functions (PR#13588)
On 10/03/2009 4:35 PM, michael_ka...@earthlink.net wrote: Full_Name: Michael Aaron Karsh Version: 2.8.0 OS: Windows XP Submission from: (NULL) (164.67.71.215) When I try to say if (method==f), where f is a function, it says that the comparison is only possible for list and atomic types. I tried saying if (method!=f), and it gave the same error message. Would it be possible to repair it say that == and != comparisons would be possible for functions? This is not a bug. Please don't report things as bugs when they aren't. "==" and "!=" are for atomic vectors, as documented. Use identical() for more general comparisons, as documented on the man page for ==. Duncan Murdoch __ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
[Rd] logical comparison of functions (PR#13588)
Full_Name: Michael Aaron Karsh Version: 2.8.0 OS: Windows XP Submission from: (NULL) (164.67.71.215) When I try to say if (method==f), where f is a function, it says that the comparison is only possible for list and atomic types. I tried saying if (method!=f), and it gave the same error message. Would it be possible to repair it say that == and != comparisons would be possible for functions? __ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
