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| /** | |
| * SetArray acts like a `Set` (allowing only one occurrence of a string `key`), but provides the | |
| * index of the `key` in the backing array. | |
| * | |
| * This is designed to allow synchronizing a second array with the contents of the backing array, | |
| * like how in a sourcemap `sourcesContent[i]` is the source content associated with `source[i]`, | |
| * and there are never duplicates. | |
| */ | |
| class SetArray { | |
| constructor() { | |
| this._indexes = { __proto__: null }; | |
| this.array = []; | |
| } | |
| } | |
| /** | |
| * Typescript doesn't allow friend access to private fields, so this just casts the set into a type | |
| * with public access modifiers. | |
| */ | |
| function cast(set) { | |
| return set; | |
| } | |
| /** | |
| * Gets the index associated with `key` in the backing array, if it is already present. | |
| */ | |
| function get(setarr, key) { | |
| return cast(setarr)._indexes[key]; | |
| } | |
| /** | |
| * Puts `key` into the backing array, if it is not already present. Returns | |
| * the index of the `key` in the backing array. | |
| */ | |
| function put(setarr, key) { | |
| // The key may or may not be present. If it is present, it's a number. | |
| const index = get(setarr, key); | |
| if (index !== undefined) | |
| return index; | |
| const { array, _indexes: indexes } = cast(setarr); | |
| const length = array.push(key); | |
| return (indexes[key] = length - 1); | |
| } | |
| /** | |
| * Pops the last added item out of the SetArray. | |
| */ | |
| function pop(setarr) { | |
| const { array, _indexes: indexes } = cast(setarr); | |
| if (array.length === 0) | |
| return; | |
| const last = array.pop(); | |
| indexes[last] = undefined; | |
| } | |
| /** | |
| * Removes the key, if it exists in the set. | |
| */ | |
| function remove(setarr, key) { | |
| const index = get(setarr, key); | |
| if (index === undefined) | |
| return; | |
| const { array, _indexes: indexes } = cast(setarr); | |
| for (let i = index + 1; i < array.length; i++) { | |
| const k = array[i]; | |
| array[i - 1] = k; | |
| indexes[k]--; | |
| } | |
| indexes[key] = undefined; | |
| array.pop(); | |
| } | |
| export { SetArray, get, pop, put, remove }; | |
| //# sourceMappingURL=set-array.mjs.map | |