Dear All,
I came across an error message recently when constructing a reference class,
an example is attached below, it looks like only if I call a specific method
in advance, otherwise it cannot be found in defined method without using
.self, this make it difficulty that sometimes in my initialize method, I
need to call other method defined in the same reference class, the
workaround for this is add .sef to it.
############### example begin ############################
setRefClass("testclass", fields = list(a = "numeric"),
methods = list(
addOne = function(){
a <<- a+1
print(a)
},
add = function(){
addOne()
},
show = function(){
print(addOne)
},
showself = function(){
print(.self$addOne)
}
))
obj <- new("testclass", a = 1)
obj$show() #
Error in print(addOne) : object 'addOne' not found
obj$addOne() #
return 2, works
obj$show() #
after calling addOne(), show() works
## works if use .self$...
obj2 <- new("testclass", a = 1)
obj2$showself()
## works when call the method directly within another method
obj3 <- new("testclass", a = 1)
obj3$add()
################ end ##########################################
I am still learning this new technique, if I made any mistake I didn't
notice before, please let me know, I will really appreciate that.
Thanks a lot!
Tengfei
--
Tengfei Yin
MCDB PhD student
1620 Howe Hall, 2274,
Iowa State University
Ames, IA,50011-2274
Homepage: www.tengfei.name
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