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I have an object, suppose it's called obj. I can call a function, obj$a() and that works. However, when I call obj$b(), which internally calls self$a(), it throws an error saying that it cannot find the a function. What can I do?

Shan Tulshi
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    Might be helpful if you posted some code to make your problem reproducible. – Slavatron Aug 10 '16 at 18:49
  • R's OOP is not so fancy as all that, as far as I know. You probably want to just go `with(obj, ... do stuff ...)`. – Frank Aug 10 '16 at 18:50
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    `self` isn't really a thing in R... – Gregor Thomas Aug 10 '16 at 18:51
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    I'm pretty unknowledgeable about this stuff but `obj = within(list(), { a = function(x) 2*x; b = function(x,y) a(x) + y })` "works", in the sense that I can do `obj$b(11,22)`. This Q&A might be helpful: http://stackoverflow.com/questions/9521651/r-and-object-oriented-programming – Frank Aug 10 '16 at 18:52

1 Answers1

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You need to make sure that the functions share an environment / are in the same closure. You could encapsulate them in a dummy function. Look at this example:

gives_error <- list(a = function() { 
                          print("Hello from a")
                        },
                    b = function(){
                          print("Hello from b")
                          a()
                    })

gives_error$b()


will_work <-
    (function() {
        a = function(){ 
            print("Hello from a")
        }
        b = function(){
            print("Hello from b")
            a()
        }
        list(a = a, b = b)
    })()

will_work$b()
AEF
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