CODEWITHSUNDEEP
roopmethodsreference-class
Rappster
Rappster

Reputation: 13080

Listing explicitly defined methods only (Reference Classes)

Is there a way to list only those methods of a Reference Class, that were explicitly defined in the class definition (as opposed to those methods inherited by "system classes" such as refObjectGenerator or envRefClass)?

Example <- setRefClass(
    Class="Example",
    fields=list(
    ),
    methods=list(
        testMethodA=function() {
            "Test method A"
        },
        testMethodB=function() {
            "Test method B"
        }
    )
)

What you currently get by calling the $methods() method (see ?setRefClass):

> Example$methods()
 [1] "callSuper"    "copy"         "export"       "field"        "getClass"    
 [6] "getRefClass"  "import"       "initFields"   "show"         "testMethodA" 
[11] "testMethodB"  "trace"        "untrace"      "usingMethods"

What I'm looking for: 

> Example$methods()
 [1] "testMethodA" "testMethodB"

Upvotes: 4

Views: 107

Answers (2)

G. Grothendieck
G. Grothendieck

Reputation: 269634

1) Try this:

> Dummy <- setRefClass(Class = "dummy")
> setdiff(Example$methods(), Dummy$methods())
[1] "testMethodA" "testMethodB"

2) Here is a second approach which seems to work here but you might want to test it out more:

names(Filter(function(x) attr(x, "refClassName") == Example$className, 
    as.list(Example$def@refMethods)))

Upvotes: 3

hadley
hadley

Reputation: 103898

No, because the methods in a reference class "inherited" from the parent are actually copied into the class when it is generated.

setRefClass("Example", methods = list(
  a = function() {}, 
  b = function() {}
))

class <- getClass("Example")
ls(class@refMethods)
#> [1]  "a"            "b"            "callSuper"    "copy"         "export"      
#> [6]  "field"        "getClass"     "getRefClass"  "import"       "initFields"  
#> [11] "show"         "trace"        "untrace"      "usingMethods"

But you can find out the method also defined in the parent and return those:

parent <- getClass(class@refSuperClasses)
ls(parent@refMethods)
#> [1]  "callSuper"    "copy"         "export"       "field"        "getClass"    
#> [6]  "getRefClass"  "import"       "initFields"   "show"         "trace"       
#> [11] "untrace"      "usingMethods"

(note that I'm ignoring the possibility that your class has multiple parents, but that would be easy to generalise)

And then use setdiff() to find the difference

setdiff(ls(class@refMethods), ls(parent@refMethods))
#> [1] "a" "b"

Upvotes: 2

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