code.delx.au - gnu-emacs-elpa/blob - NEWS.md

   1 # History of user-visible changes
   2
   3 ## Next
   4
   5 * Object properties are highlighted using a different face:
   6   `js2-object-property`, which has no color by default.
   7 * `js2-getter-setter-node` is renamed to `js2-method-node`, together with
   8   its related functions.  It already handles generator methods, and we
   9   added support for async methods (see below), so the old name will get
  10   more confusing.
  11 * Support for default parameters in destructuring.  It should work for both
  12   objects and arrays, in both literals and function arguments.
  13 * New mode: `js2-jsx-mode`, deriving from `js2-mode`.  Supports indentation of
  14   JSXElement expressions wrapped within parentheses or as function arguments.
  15   Indentation is customizable via `sgml-attribute-offset`.
  16 * Experimental support for ES7 stage 3 async/await.
  17
  18 ## 20150909
  19
  20 * `js2-mode` now derives from `js-mode`. That means the former
  21   function will run `js-mode-hook`, as well as `js2-mode-hook`. The
  22   key bindings will default to `js-mode-map` where they're not set in
  23   `js2-mode-map`. And in Emacs 25 or later (including the snapshot
  24   builds), `js2-mode` uses the indentation code from `js-mode`.  Where
  25   feasible, the user options (and functions) now have aliases, but if
  26   you're using Emacs 25 and you see an indentation-related setting
  27   that stopped working, try looking for a corresponding one in the
  28   `js` group: `M-x customize-group RET js RET`.
  29
  30 * New command: `js2-jump-to-definition`. It's bound to `M-.` by
  31   default, via remapping `js-find-symbol`. To get back to the default
  32   `M-.` binding (e.g. `find-tag`), put this in your init file:
  33
  34       (eval-after-load 'js (define-key js-mode-map (kbd "M-.") nil))
  35
  36 ## 20150713
  37
  38 * More comprehensive strict mode warnings and syntax errors.
  39 * New minor mode: `js2-highlight-unused-variables-mode`.
  40 * `js2-pretty-multiline-declarations` can take the value `dynamic` now.
  41
  42 ## 20150202
  43
  44 Support for:
  45
  46 * [ES6 modules](http://www.2ality.com/2014/09/es6-modules-final.html).
  47 * [Short-hand object literals](http://ariya.ofilabs.com/2013/02/es6-and-object-literal-property-value-shorthand.html).
  48 * [Method definitions](http://ariya.ofilabs.com/2013/03/es6-and-method-definitions.html).
  49 * ['u' and 'y' RegExp flags](https://mathiasbynens.be/notes/es6-unicode-regex).
  50 * [Computed property names](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-object-initializer).
  51 * [Class statements and expressions](https://github.com/lukehoban/es6features#classes).
  52 * [Template strings](http://tc39wiki.calculist.org/es6/template-strings/), including tagged ones.
  53
  54 The variable `js2-allow-keywords-as-property-names` has been
  55 removed. Instead we check if `js2-language-version` is 180 or highter.
  56
  57 ## 20141115
  58
  59 Support for:
  60
  61 * Unicode characters in identifiers (improved).
  62 * [Delegating yield](http://wiki.ecmascript.org/doku.php?id=harmony:generators#delegating_yield).
  63 * [ES6 numeric literals](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-literals-numeric-literals) (octal, binary).
  64 * Harmony [array and generator comprehensions](http://wingolog.org/archives/2014/03/07/es6-generator-and-array-comprehensions-in-spidermonkey).
  65
  66 ## 20131106
  67
  68 Support for:
  69
  70 * [Arrow functions](http://wiki.ecmascript.org/doku.php?id=harmony:arrow_function_syntax)
  71 * [Generators](http://wiki.ecmascript.org/doku.php?id=harmony:generators)
  72 * [Spread operator](http://wiki.ecmascript.org/doku.php?id=harmony:spread)
  73
  74 ## 20130510
  75
  76 ### Support for JSLint global declaration
  77
  78 See the docstring for `js2-include-jslint-globals`.
  79
  80 ## 20130216
  81
  82 ### We don't rebind `RET` anymore
  83
  84 Because well-behaving major modes aren't supposed to do that.
  85
  86 So pressing it won't continue a block comment, or turn a string into a concatenation.
  87 Pressing `M-j`, however, will.
  88
  89 The options `js2-indent-on-enter-key` and `js2-enter-indents-newline` were also removed.
  90
  91 To bring back the previous behavior, put this in your init file:
  92
  93 ```js
  94 (eval-after-load 'js2-mode
  95   '(define-key js2-mode-map (kbd "RET") 'js2-line-break))
  96 ```
  97
  98 ## 20120617
  99
 100 ### Support for [default](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/default_parameters) and [rest](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/rest_parameters) parameters
 101
 102 ## 20120614
 103
 104 ### Support for [for..of loops](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...of)
 105
 106 ## Older changes
 107
 108 ### Popular indentation style
 109
 110 ```js
 111 [foo, bar, baz].forEach(function (v) {
 112     if (validate(v))
 113         process(v);
 114 });
 115
 116 [a, b, c].some(function (v) {
 117     return validate(v);
 118 });
 119 ```
 120
 121 ### Pretty multiline variable declaration
 122
 123 In the original mode,
 124
 125 ```js
 126 var foo = 10,
 127 bar = 20,
 128 baz = 30;
 129 ```
 130
 131 In this mode when the value of `js2-pretty-multiline-declarations` is non-nil,
 132
 133 ```js
 134 var foo = 10,
 135     bar = 20,
 136     baz = 30;
 137 ```
 138
 139 ### Abbreviated destructuring assignments
 140
 141 ```js
 142 let {a, b}       = {a: 10, b: 20}; // Abbreviated   (Not supported in the original mode)
 143 let {a: a, b: b} = {a: 10, b: 20}; // Same as above (Supported in the original mode)
 144
 145 (function ({responseText}) { /* */ })(xhr); // As the argument of function
 146
 147 for (let [k, { name, age }] in Iterator(obj)) // nested
 148     print(k, name, age);
 149 ```
 150
 151 ### Expression closure in property value
 152
 153 ```js
 154 let worker = {
 155     get age() 20,
 156     get sex() "male",
 157     fire: function () _fire()
 158 };
 159 ```
 160
 161 ### Fix for odd indentation of "else if" with no braces
 162
 163 In the original mode,
 164
 165 ```js
 166 if (foo)
 167     return foo;
 168 else if (bar)
 169 return bar;      // here
 170 ```
 171
 172 In this mode,
 173
 174 ```js
 175 if (foo)
 176     return foo;
 177 else if (bar)
 178     return bar;  // fixed
 179 ```
 180
 181 ### Imenu support for function nesting
 182
 183 Supports function nesting and anonymous wrappers:
 184
 185 ```js
 186 (function() {
 187   var foo = function() {
 188     function bar() { // shown as foo.bar.<definition-1>
 189       function baz() {} // foo.bar.baz
 190       var qux = function() {}; // foo.bar.quux
 191     }
 192   };
 193 });
 194 ```
 195
 196 Examples of output:
 197
 198 * [jQuery 1.5](https://gist.github.com/845449)
 199 * [Underscore.js](https://gist.github.com/824262)
 200 * [Backbone.js](https://gist.github.com/824260)
 201
 202 For library-specific extension methods like `$.extend` and `dojo.declare`, see [js2-imenu-extras](/mooz/js2-mode/blob/master/js2-imenu-extras.el).
 203
 204 ### Undeclared/external variables highlighting
 205
 206 Original mode highlights them only on the left side of assignments:
 207
 208 ```js
 209 var house;
 210 hose = new House(); // highlights "hose"
 211 ```
 212
 213 Here they are highlighted in all expressions:
 214
 215 ```js
 216 function feed(fishes, food) {
 217     for each (var fish in fshes) { // highlights "fshes"
 218         food.feed(fsh); // highlights "fsh"
 219     }
 220     hood.discard(); // highlights "hood"
 221 }
 222 ```
 223
 224 Destructuring assignments and array comprehensions (JS 1.7) are supported:
 225
 226 ```js
 227 let three, [one, two] = [1, 2];
 228 thee = one + two; // highlights "thee"
 229
 230 function revenue(goods) {
 231     // highlights "coast"
 232     return [price - coast for each ({price, cost} in goods)].reduce(add);
 233 }
 234 ```