tree_root_node_with_offset() is similar to tree_root_node(),
but the returned root node's position has been shifted by the given number of
bytes, rows, and columns.
This function allows you to parse a subset of a document with
parser_parse() as if it were a self-contained document, but then later
access the syntax tree in the coordinate space of the larger document.
Note that the underlying text within x is not what you are offsetting
into. Instead, you should assume that the text you provided to
parser_parse() already contained the entire subset of the document you care
about, and the offset you are providing is how far into the document the
beginning of text is.
Arguments
- x
[tree_sitter_tree]A tree.
- byte, point
[double(1), tree_sitter_point]A byte and point offset combination.
Examples
language <- treesitter.r::language()
parser <- parser(language)
text <- "fn <- function() { 1 + 1 }"
tree <- parser_parse(parser, text)
# If `text` was the whole document, you can just use `tree_root_node()`
node <- tree_root_node(tree)
# If `text` represents a subset of the document, use
# `tree_root_node_with_offset()` to be able to get positions in the
# coordinate space of the original document.
byte <- 5
point <- point(5, 0)
node_offset <- tree_root_node_with_offset(tree, byte, point)
# The position of `fn` if you treat `text` as the whole document
node |>
node_child(1) |>
node_child(1)
#> <tree_sitter_node>
#>
#> ── Text ──────────────────────────────────────────────────────────────────
#> fn
#>
#> ── S-Expression ──────────────────────────────────────────────────────────
#> (identifier [(0, 0), (0, 2)])
# The position of `fn` if you treat `text` as a subset of a larger document
node_offset |>
node_child(1) |>
node_child(1)
#> <tree_sitter_node>
#>
#> ── Text ──────────────────────────────────────────────────────────────────
#> fn
#>
#> ── S-Expression ──────────────────────────────────────────────────────────
#> (identifier [(5, 0), (5, 2)])