Built a path dynamically from a nested List

Question

Having this nested list:

myList<-list()
myList[[length(myList)+1]]<-list(text="Grandfather01",tabName='tabnameGrandfather01')
myList[[length(myList)+1]]<-list(text="Grandfather02",
                                 list(text="Father02_01"
                                      ,list(text='Child02_01_01',tabName='tabNameChild02_01_01')
                                      ,list(text='Child02_01_02',tabName='tabNameChild02_01_02')
                                 )
                                )
myList[[length(myList)+1]]<-list(text="Grandfather03",
                                 list(text='Father03_01',tabName='tabNameFather03_01')
                              )

myList[[length(myList)+1]]<-list(text="Grandfather04"
                                 ,list(text="Father04_01"
                                       ,list(text='Child04_01_01'
                                             ,list(text='SuperChild04_01_01_01',tabName='tabNameSuperChild04_01_01_01')
                                             ,list(text='SuperChild04_01_01_02',tabName='tabNameSuperChild04_01_01_02')
                                       )      
                                 )
                                 ,list(text='Father05_01',tabName='tabNameFather05_01')
                              )

I need to build a list of paths such as:

the first element contains:

/tabnameGrandfather01

the second element contains:

Grandfather02/Father02_01/tabNameChild02_01_01
Grandfather02/Father02_01/tabNameChild02_01_02

the third element contains:

Grandfather03/tabNameFather03_01

the last one contains:

Grandfather04/Father04_01/Child04_01_01/tabNameSuperChild04_01_01_01
Grandfather04/Father04_01/Child04_01_01/tabNameSuperChild04_01_01_02
Grandfather04/tabNameFather05_01

Any idea using recursive function?

Answer 1

You can try this recursive function:

collapse <- function(x, root = NULL) {
    path <-
        if (length(x) == 2L && identical(names(x), c("text", "tabName")))
            x[[2L]]
        else unlist(lapply(x[-1L], sys.function(), x[[1L]]), FALSE, FALSE)
    if (is.null(root)) path else file.path(root, path)
}

lapply(myList, collapse)

[[1]]
[1] "tabnameGrandfather01"

[[2]]
[1] "Grandfather02/Father02_01/tabNameChild02_01_01"
[2] "Grandfather02/Father02_01/tabNameChild02_01_02"

[[3]]
[1] "Grandfather03/tabNameFather03_01"

[[4]]
[1] "Grandfather04/Father04_01/Child04_01_01/tabNameSuperChild04_01_01_01"
[2] "Grandfather04/Father04_01/Child04_01_01/tabNameSuperChild04_01_01_02"
[3] "Grandfather04/tabNameFather05_01"