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

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