How to find an object within multiple rdata files

Question

I am trying to find a way that I can search a folder containing many RData and RDA files to find a specific object that I have forgotten in which RDA file it exists.
Thank you.

Answer 1

You can load a .RData file (is that the same as an RDA file?) into an environment and then test if a name is present with this function:

 hasgot=function(f,name){
      e=new.env()
      load(f,env=e)
      name %in% ls(env=e,all.names=TRUE)
      }

The following variation might be faster:

 hasgot=function(f,name){
      e=new.env()
      load(f,env=e)
      !is.null(e[[name]])
      }

Usage is simply hasgot("my.RData","foo") to see if foo is in my.RData . Its not vectorised over either argument, so only feed it one thing at a time.

A full solution for your problem will probably involve wrapping this in list.files and a loop.