node_type() returns the "type" of the current node as a string.
This is a very useful function for making decisions about how to handle the current node.
Examples
language <- treesitter.r::language()
parser <- parser(language)
text <- "fn <- function() { 1 + 1 }"
tree <- parser_parse(parser, text)
node <- tree_root_node(tree)
# Top level program node
node_type(node)
#> [1] "program"
# The whole `<-` binary operator node
node <- node_child(node, 1)
node
#> <tree_sitter_node>
#>
#> ── Text ──────────────────────────────────────────────────────────────────
#> fn <- function() { 1 + 1 }
#>
#> ── S-Expression ──────────────────────────────────────────────────────────
#> (binary_operator [(0, 0), (0, 26)]
#> lhs: (identifier [(0, 0), (0, 2)])
#> operator: "<-" [(0, 3), (0, 5)]
#> rhs: (function_definition [(0, 6), (0, 26)]
#> name: "function" [(0, 6), (0, 14)]
#> parameters: (parameters [(0, 14), (0, 16)]
#> open: "(" [(0, 14), (0, 15)]
#> close: ")" [(0, 15), (0, 16)]
#> )
#> body: (braced_expression [(0, 17), (0, 26)]
#> open: "{" [(0, 17), (0, 18)]
#> body: (binary_operator [(0, 19), (0, 24)]
#> lhs: (float [(0, 19), (0, 20)])
#> operator: "+" [(0, 21), (0, 22)]
#> rhs: (float [(0, 23), (0, 24)])
#> )
#> close: "}" [(0, 25), (0, 26)]
#> )
#> )
#> )
node_type(node)
#> [1] "binary_operator"
# Just the literal `<-` operator itself
node <- node_child_by_field_name(node, "operator")
node
#> <tree_sitter_node>
#>
#> ── Text ──────────────────────────────────────────────────────────────────
#> <-
#>
#> ── S-Expression ──────────────────────────────────────────────────────────
#> "<-" [(0, 3), (0, 5)]
node_type(node)
#> [1] "<-"