switch to vuepress

1 files changed, 324 insertions, 0 deletions

diff --git a/node_modules/vue/src/shared/util.js b/node_modules/vue/src/shared/util.js
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--- /dev/null
+++ b/node_modules/vue/src/shared/util.js
@@ -0,0 +1,324 @@
+/* @flow */
+
+export const emptyObject = Object.freeze({})
+
+// these helpers produces better vm code in JS engines due to their
+// explicitness and function inlining
+export function isUndef (v: any): boolean %checks {
+  return v === undefined || v === null
+}
+
+export function isDef (v: any): boolean %checks {
+  return v !== undefined && v !== null
+}
+
+export function isTrue (v: any): boolean %checks {
+  return v === true
+}
+
+export function isFalse (v: any): boolean %checks {
+  return v === false
+}
+
+/**
+ * Check if value is primitive
+ */
+export function isPrimitive (value: any): boolean %checks {
+  return (
+    typeof value === 'string' ||
+    typeof value === 'number' ||
+    // $flow-disable-line
+    typeof value === 'symbol' ||
+    typeof value === 'boolean'
+  )
+}
+
+/**
+ * Quick object check - this is primarily used to tell
+ * Objects from primitive values when we know the value
+ * is a JSON-compliant type.
+ */
+export function isObject (obj: mixed): boolean %checks {
+  return obj !== null && typeof obj === 'object'
+}
+
+/**
+ * Get the raw type string of a value e.g. [object Object]
+ */
+const _toString = Object.prototype.toString
+
+export function toRawType (value: any): string {
+  return _toString.call(value).slice(8, -1)
+}
+
+/**
+ * Strict object type check. Only returns true
+ * for plain JavaScript objects.
+ */
+export function isPlainObject (obj: any): boolean {
+  return _toString.call(obj) === '[object Object]'
+}
+
+export function isRegExp (v: any): boolean {
+  return _toString.call(v) === '[object RegExp]'
+}
+
+/**
+ * Check if val is a valid array index.
+ */
+export function isValidArrayIndex (val: any): boolean {
+  const n = parseFloat(String(val))
+  return n >= 0 && Math.floor(n) === n && isFinite(val)
+}
+
+/**
+ * Convert a value to a string that is actually rendered.
+ */
+export function toString (val: any): string {
+  return val == null
+    ? ''
+    : typeof val === 'object'
+      ? JSON.stringify(val, null, 2)
+      : String(val)
+}
+
+/**
+ * Convert a input value to a number for persistence.
+ * If the conversion fails, return original string.
+ */
+export function toNumber (val: string): number | string {
+  const n = parseFloat(val)
+  return isNaN(n) ? val : n
+}
+
+/**
+ * Make a map and return a function for checking if a key
+ * is in that map.
+ */
+export function makeMap (
+  str: string,
+  expectsLowerCase?: boolean
+): (key: string) => true | void {
+  const map = Object.create(null)
+  const list: Array<string> = str.split(',')
+  for (let i = 0; i < list.length; i++) {
+    map[list[i]] = true
+  }
+  return expectsLowerCase
+    ? val => map[val.toLowerCase()]
+    : val => map[val]
+}
+
+/**
+ * Check if a tag is a built-in tag.
+ */
+export const isBuiltInTag = makeMap('slot,component', true)
+
+/**
+ * Check if a attribute is a reserved attribute.
+ */
+export const isReservedAttribute = makeMap('key,ref,slot,slot-scope,is')
+
+/**
+ * Remove an item from an array
+ */
+export function remove (arr: Array<any>, item: any): Array<any> | void {
+  if (arr.length) {
+    const index = arr.indexOf(item)
+    if (index > -1) {
+      return arr.splice(index, 1)
+    }
+  }
+}
+
+/**
+ * Check whether the object has the property.
+ */
+const hasOwnProperty = Object.prototype.hasOwnProperty
+export function hasOwn (obj: Object | Array<*>, key: string): boolean {
+  return hasOwnProperty.call(obj, key)
+}
+
+/**
+ * Create a cached version of a pure function.
+ */
+export function cached<F: Function> (fn: F): F {
+  const cache = Object.create(null)
+  return (function cachedFn (str: string) {
+    const hit = cache[str]
+    return hit || (cache[str] = fn(str))
+  }: any)
+}
+
+/**
+ * Camelize a hyphen-delimited string.
+ */
+const camelizeRE = /-(\w)/g
+export const camelize = cached((str: string): string => {
+  return str.replace(camelizeRE, (_, c) => c ? c.toUpperCase() : '')
+})
+
+/**
+ * Capitalize a string.
+ */
+export const capitalize = cached((str: string): string => {
+  return str.charAt(0).toUpperCase() + str.slice(1)
+})
+
+/**
+ * Hyphenate a camelCase string.
+ */
+const hyphenateRE = /\B([A-Z])/g
+export const hyphenate = cached((str: string): string => {
+  return str.replace(hyphenateRE, '-$1').toLowerCase()
+})
+
+/**
+ * Simple bind polyfill for environments that do not support it... e.g.
+ * PhantomJS 1.x. Technically we don't need this anymore since native bind is
+ * now more performant in most browsers, but removing it would be breaking for
+ * code that was able to run in PhantomJS 1.x, so this must be kept for
+ * backwards compatibility.
+ */
+
+/* istanbul ignore next */
+function polyfillBind (fn: Function, ctx: Object): Function {
+  function boundFn (a) {
+    const l = arguments.length
+    return l
+      ? l > 1
+        ? fn.apply(ctx, arguments)
+        : fn.call(ctx, a)
+      : fn.call(ctx)
+  }
+
+  boundFn._length = fn.length
+  return boundFn
+}
+
+function nativeBind (fn: Function, ctx: Object): Function {
+  return fn.bind(ctx)
+}
+
+export const bind = Function.prototype.bind
+  ? nativeBind
+  : polyfillBind
+
+/**
+ * Convert an Array-like object to a real Array.
+ */
+export function toArray (list: any, start?: number): Array<any> {
+  start = start || 0
+  let i = list.length - start
+  const ret: Array<any> = new Array(i)
+  while (i--) {
+    ret[i] = list[i + start]
+  }
+  return ret
+}
+
+/**
+ * Mix properties into target object.
+ */
+export function extend (to: Object, _from: ?Object): Object {
+  for (const key in _from) {
+    to[key] = _from[key]
+  }
+  return to
+}
+
+/**
+ * Merge an Array of Objects into a single Object.
+ */
+export function toObject (arr: Array<any>): Object {
+  const res = {}
+  for (let i = 0; i < arr.length; i++) {
+    if (arr[i]) {
+      extend(res, arr[i])
+    }
+  }
+  return res
+}
+
+/**
+ * Perform no operation.
+ * Stubbing args to make Flow happy without leaving useless transpiled code
+ * with ...rest (https://flow.org/blog/2017/05/07/Strict-Function-Call-Arity/)
+ */
+export function noop (a?: any, b?: any, c?: any) {}
+
+/**
+ * Always return false.
+ */
+export const no = (a?: any, b?: any, c?: any) => false
+
+/**
+ * Return same value
+ */
+export const identity = (_: any) => _
+
+/**
+ * Generate a static keys string from compiler modules.
+ */
+export function genStaticKeys (modules: Array<ModuleOptions>): string {
+  return modules.reduce((keys, m) => {
+    return keys.concat(m.staticKeys || [])
+  }, []).join(',')
+}
+
+/**
+ * Check if two values are loosely equal - that is,
+ * if they are plain objects, do they have the same shape?
+ */
+export function looseEqual (a: any, b: any): boolean {
+  if (a === b) return true
+  const isObjectA = isObject(a)
+  const isObjectB = isObject(b)
+  if (isObjectA && isObjectB) {
+    try {
+      const isArrayA = Array.isArray(a)
+      const isArrayB = Array.isArray(b)
+      if (isArrayA && isArrayB) {
+        return a.length === b.length && a.every((e, i) => {
+          return looseEqual(e, b[i])
+        })
+      } else if (!isArrayA && !isArrayB) {
+        const keysA = Object.keys(a)
+        const keysB = Object.keys(b)
+        return keysA.length === keysB.length && keysA.every(key => {
+          return looseEqual(a[key], b[key])
+        })
+      } else {
+        /* istanbul ignore next */
+        return false
+      }
+    } catch (e) {
+      /* istanbul ignore next */
+      return false
+    }
+  } else if (!isObjectA && !isObjectB) {
+    return String(a) === String(b)
+  } else {
+    return false
+  }
+}
+
+export function looseIndexOf (arr: Array<mixed>, val: mixed): number {
+  for (let i = 0; i < arr.length; i++) {
+    if (looseEqual(arr[i], val)) return i
+  }
+  return -1
+}
+
+/**
+ * Ensure a function is called only once.
+ */
+export function once (fn: Function): Function {
+  let called = false
+  return function () {
+    if (!called) {
+      called = true
+      fn.apply(this, arguments)
+    }
+  }
+}