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

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