Get line and column of YAML element given by JSON Pointer

In a Node project I have a YAML (or subset JSON) document as input and a validation function that returns a JSON Pointer of an element in the parsed document. For instance this YAML document:

a: 1
b:
  - 42
  - foo # comment

Has possible elements /a, /b, /b/0, and /b/1. Given an element pointer, how can I get the line(s) and column(s) of the corresponding element in the input document? For instance element /b/1 is on line 4, columns 4 to 6.

Meanwhile I found a solution like this to get the position of the element value:

import { parseDocument, YAMLSeq, YAMLMap } from "yaml"

// get line and column from character offset
function lineCol(str, offset) {
  const lines = str.slice(0, offset).split("\n")
  return {
    line: lines.length,
    col: lines[lines.length - 1].length + 1,
  }
}

export function yamlPosition(doc, path) {
  let node = parseDocument(doc, { keepSourceTokens: true }).contents

  // parse JSON Pointer
  path = path.split("/").slice(1).map(s => s.replace(/~1/g, "/").replace(/~0/g, "~"))

  while (node && path.length) {
    const elem = path.shift()
    if (node instanceof YAMLSeq) {
      node = node.items[Number(elem)]
    } else if (node instanceof YAMLMap) {
      node = node.get(elem, true)
    } else {
      return // element not found
    }
    if (node && !path.length) {
      return node.range.slice(0,2).map(offset => lineCol(doc, offset))
    }
  }
}

Getting the full element (internal node Pair) requires some change to the function but it is similar.