Cannot unlist a list coerced from a call object in R? -

here experiment:

myfunc = function(a, b, c) {     callobj = match.call()     save(callobj, file="/tmp/callobj.rda") } myfunc(11, 22, 33) load("/tmp/callobj.rda") x = unlist(as.list(callobj)) print(x) x = unlist(list(a = 1, b = 2, c = 3)) print(x) 

results:

> myfunc(11, 22, 33) > load("/tmp/callobj.rda") > x = unlist(as.list(callobj)) > print(x) [[1]] myfunc  $a [1] 11  $b [1] 22  $c [1] 33  > x = unlist(list(a = 1, b = 2, c = 3)) > print(x) b c  1 2 3 

the question is, why on earth 2 lists behave differently? 1 of them can unlisted, other, apparently, cannot.

as suggested in 1 of comments, did this:

> dput(as.list(callobj)) structure(list(myfunc, = 11, b = 22, c = 33), .names = c("",  "a", "b", "c")) > dput(list(a = 1, b = 2)) structure(list(a = 1, b = 2), .names = c("a", "b")) 

doesn't explain why 2 lists different in behavior.

you can use as.character on call objects.

this equivalent unlisted, unnamed call as.list(callobj).

> as.character(callobj) # [1] "myfunc" "11"     "22"     "33"   

to unlist callobj, need elements of same type. can't have characters, numerics, , calls in same vector. r not allow mixed object types in same vector.

but can use deparse , done:

> sapply(as.list(callobj), deparse) #                        b        c  # "myfunc"     "11"     "22"     "33"  

this makes apparent 1 of main differences between sapply , lapply. don't need unlist if use sapply.