Top-Level Child Names — tree_child

The names of a list tree's top-level children (with "" for unnamed slots), or NULL if the root is not a list node or carries no names.

Usage

tree_child_names(tree)

Arguments

tree: (RTree)
A tree as returned by build_tree().

Value

A character vector of child names, or NULL when the root is not a list node or is an unnamed list. An empty but named list (structure(list(), names = character(0))) returns character(0), not NULL: the tree preserves the named/unnamed distinction (see tree_equal()).

Examples

tree_child_names(build_tree(list(a = 1, b = 2)))
#> [1] "a" "b"
tree_child_names(build_tree(list(1, 2)))
#> NULL