implemented frontend including separate message system; started to implement backend

yjs-poll/node_modules/lib0/array.js

@@ -0,0 +1,219 @@
+/**
+ * Utility module to work with Arrays.
+ *
+ * @module array
+ */
+
+import * as set from './set.js'
+
+/**
+ * Return the last element of an array. The element must exist
+ *
+ * @template L
+ * @param {ArrayLike<L>} arr
+ * @return {L}
+ */
+export const last = arr => arr[arr.length - 1]
+
+/**
+ * @template C
+ * @return {Array<C>}
+ */
+export const create = () => /** @type {Array<C>} */ ([])
+
+/**
+ * @template D
+ * @param {Array<D>} a
+ * @return {Array<D>}
+ */
+export const copy = a => /** @type {Array<D>} */ (a.slice())
+
+/**
+ * Append elements from src to dest
+ *
+ * @template M
+ * @param {Array<M>} dest
+ * @param {Array<M>} src
+ */
+export const appendTo = (dest, src) => {
+  for (let i = 0; i < src.length; i++) {
+    dest.push(src[i])
+  }
+}
+
+/**
+ * Transforms something array-like to an actual Array.
+ *
+ * @function
+ * @template T
+ * @param {ArrayLike<T>|Iterable<T>} arraylike
+ * @return {T}
+ */
+export const from = Array.from
+
+/**
+ * True iff condition holds on every element in the Array.
+ *
+ * @function
+ * @template {ArrayLike<any>} ARR
+ *
+ * @param {ARR} arr
+ * @param {ARR extends ArrayLike<infer S> ? ((value:S, index:number, arr:ARR) => boolean) : any} f
+ * @return {boolean}
+ */
+export const every = (arr, f) => {
+  for (let i = 0; i < arr.length; i++) {
+    if (!f(arr[i], i, arr)) {
+      return false
+    }
+  }
+  return true
+}
+
+/**
+ * True iff condition holds on some element in the Array.
+ *
+ * @function
+ * @template {ArrayLike<any>} ARR
+ *
+ * @param {ARR} arr
+ * @param {ARR extends ArrayLike<infer S> ? ((value:S, index:number, arr:ARR) => boolean) : never} f
+ * @return {boolean}
+ */
+export const some = (arr, f) => {
+  for (let i = 0; i < arr.length; i++) {
+    if (f(arr[i], i, arr)) {
+      return true
+    }
+  }
+  return false
+}
+
+/**
+ * @template ELEM
+ *
+ * @param {ArrayLike<ELEM>} a
+ * @param {ArrayLike<ELEM>} b
+ * @return {boolean}
+ */
+export const equalFlat = (a, b) => a.length === b.length && every(a, (item, index) => item === b[index])
+
+/**
+ * @template ELEM
+ * @param {Array<Array<ELEM>>} arr
+ * @return {Array<ELEM>}
+ */
+export const flatten = arr => fold(arr, /** @type {Array<ELEM>} */ ([]), (acc, val) => acc.concat(val))
+
+/**
+ * @template T
+ * @param {number} len
+ * @param {function(number, Array<T>):T} f
+ * @return {Array<T>}
+ */
+export const unfold = (len, f) => {
+  const array = new Array(len)
+  for (let i = 0; i < len; i++) {
+    array[i] = f(i, array)
+  }
+  return array
+}
+
+/**
+ * @template T
+ * @template RESULT
+ * @param {Array<T>} arr
+ * @param {RESULT} seed
+ * @param {function(RESULT, T, number):RESULT} folder
+ */
+export const fold = (arr, seed, folder) => arr.reduce(folder, seed)
+
+export const isArray = Array.isArray
+
+/**
+ * @template T
+ * @param {Array<T>} arr
+ * @return {Array<T>}
+ */
+export const unique = arr => from(set.from(arr))
+
+/**
+ * @template T
+ * @template M
+ * @param {ArrayLike<T>} arr
+ * @param {function(T):M} mapper
+ * @return {Array<T>}
+ */
+export const uniqueBy = (arr, mapper) => {
+  /**
+   * @type {Set<M>}
+   */
+  const happened = set.create()
+  /**
+   * @type {Array<T>}
+   */
+  const result = []
+  for (let i = 0; i < arr.length; i++) {
+    const el = arr[i]
+    const mapped = mapper(el)
+    if (!happened.has(mapped)) {
+      happened.add(mapped)
+      result.push(el)
+    }
+  }
+  return result
+}
+
+/**
+ * @template {ArrayLike<any>} ARR
+ * @template {function(ARR extends ArrayLike<infer T> ? T : never, number, ARR):any} MAPPER
+ * @param {ARR} arr
+ * @param {MAPPER} mapper
+ * @return {Array<MAPPER extends function(...any): infer M ? M : never>}
+ */
+export const map = (arr, mapper) => {
+  /**
+   * @type {Array<any>}
+   */
+  const res = Array(arr.length)
+  for (let i = 0; i < arr.length; i++) {
+    res[i] = mapper(/** @type {any} */ (arr[i]), i, /** @type {any} */ (arr))
+  }
+  return /** @type {any} */ (res)
+}
+
+/**
+ * This function bubble-sorts a single item to the correct position. The sort happens in-place and
+ * might be useful to ensure that a single item is at the correct position in an otherwise sorted
+ * array.
+ *
+ * @example
+ *  const arr = [3, 2, 5]
+ *  arr.sort((a, b) => a - b)
+ *  arr // => [2, 3, 5]
+ *  arr.splice(1, 0, 7)
+ *  array.bubbleSortItem(arr, 1, (a, b) => a - b)
+ *  arr // => [2, 3, 5, 7]
+ *
+ * @template T
+ * @param {Array<T>} arr
+ * @param {number} i
+ * @param {(a:T,b:T) => number} compareFn
+ */
+export const bubblesortItem = (arr, i, compareFn) => {
+  const n = arr[i]
+  let j = i
+  // try to sort to the right
+  while (j + 1 < arr.length && compareFn(n, arr[j + 1]) > 0) {
+    arr[j] = arr[j + 1]
+    arr[++j] = n
+  }
+  if (i === j && j > 0) { // no change yet
+    // sort to the left
+    while (j > 0 && compareFn(arr[j - 1], n) > 0) {
+      arr[j] = arr[j - 1]
+      arr[--j] = n
+    }
+  }
+  return j
+}