| 'use strict' |
| |
| /** |
| * Expose `arrayFlatten`. |
| */ |
| module.exports = arrayFlatten |
| |
| /** |
| * Recursive flatten function with depth. |
| * |
| * @param {Array} array |
| * @param {Array} result |
| * @param {Number} depth |
| * @return {Array} |
| */ |
| function flattenWithDepth (array, result, depth) { |
| for (var i = 0; i < array.length; i++) { |
| var value = array[i] |
| |
| if (depth > 0 && Array.isArray(value)) { |
| flattenWithDepth(value, result, depth - 1) |
| } else { |
| result.push(value) |
| } |
| } |
| |
| return result |
| } |
| |
| /** |
| * Recursive flatten function. Omitting depth is slightly faster. |
| * |
| * @param {Array} array |
| * @param {Array} result |
| * @return {Array} |
| */ |
| function flattenForever (array, result) { |
| for (var i = 0; i < array.length; i++) { |
| var value = array[i] |
| |
| if (Array.isArray(value)) { |
| flattenForever(value, result) |
| } else { |
| result.push(value) |
| } |
| } |
| |
| return result |
| } |
| |
| /** |
| * Flatten an array, with the ability to define a depth. |
| * |
| * @param {Array} array |
| * @param {Number} depth |
| * @return {Array} |
| */ |
| function arrayFlatten (array, depth) { |
| if (depth == null) { |
| return flattenForever(array, []) |
| } |
| |
| return flattenWithDepth(array, [], depth) |
| } |