R: Is object a node or pairlist?

is_pairlist {rlang}

R Documentation

Is object a node or pairlist?

is_pairlist() checks that x has type pairlist.
is_node() checks that x has type pairlist or language. It tests whether x is a node that has a CAR and a CDR, including callable nodes (language objects).
is_node_list() checks that x has type pairlist or NULL. NULL is the empty node list.

is_pairlist(x)

is_node(x)

is_node_list(x)

`x`	Object to test.

These functions are experimental. We are still figuring out a good naming convention to refer to the different lisp-like lists in R.