git.r.bdr.sh - rbdr/dotfiles/blob - atom/packages/ex-mode/node_modules/event-kit/node_modules/grim/node_modules/emissary/lib/signal.js

   1 (function() {
   2   var Behavior, Emitter, Signal, Subscriber, isEqual,
   3     __hasProp = {}.hasOwnProperty,
   4     __extends = function(child, parent) { for (var key in parent) { if (__hasProp.call(parent, key)) child[key] = parent[key]; } function ctor() { this.constructor = child; } ctor.prototype = parent.prototype; child.prototype = new ctor(); child.__super__ = parent.prototype; return child; },
   5     __slice = [].slice;
   6
   7   isEqual = require('underscore-plus').isEqual;
   8
   9   Emitter = require('./emitter');
  10
  11   Subscriber = require('./subscriber');
  12
  13   Behavior = null;
  14
  15   module.exports = Signal = (function(_super) {
  16     __extends(Signal, _super);
  17
  18     Subscriber.includeInto(Signal);
  19
  20     Signal.fromEmitter = function(emitter, eventName) {
  21       return new Signal(function() {
  22         var _this = this;
  23         return this.subscribe(emitter, eventName, function() {
  24           var metadata, value;
  25           value = arguments[0], metadata = 2 <= arguments.length ? __slice.call(arguments, 1) : [];
  26           return _this.emitValue.apply(_this, [value].concat(__slice.call(metadata)));
  27         });
  28       });
  29     };
  30
  31     function Signal(subscribeCallback) {
  32       var _this = this;
  33       this.subscribeCallback = subscribeCallback;
  34       this.retainCount = 0;
  35       this.on('value-subscription-will-be-added', function() {
  36         return _this.retain();
  37       });
  38       this.on('value-subscription-removed', function() {
  39         return _this.release();
  40       });
  41     }
  42
  43     Signal.prototype.isSignal = true;
  44
  45     Signal.prototype.retained = function() {
  46       return typeof this.subscribeCallback === "function" ? this.subscribeCallback() : void 0;
  47     };
  48
  49     Signal.prototype.released = function() {
  50       return this.unsubscribe();
  51     };
  52
  53     Signal.prototype.retain = function() {
  54       if (++this.retainCount === 1) {
  55         if (typeof this.retained === "function") {
  56           this.retained();
  57         }
  58       }
  59       return this;
  60     };
  61
  62     Signal.prototype.release = function() {
  63       if (--this.retainCount === 0) {
  64         if (typeof this.released === "function") {
  65           this.released();
  66         }
  67       }
  68       return this;
  69     };
  70
  71     Signal.prototype.onValue = function(handler) {
  72       return this.on('value', handler);
  73     };
  74
  75     Signal.prototype.emitValue = function(value, metadata) {
  76       if (metadata == null) {
  77         metadata = {};
  78       }
  79       if (metadata.source == null) {
  80         metadata.source = this;
  81       }
  82       return this.emit('value', value, metadata);
  83     };
  84
  85     Signal.prototype.toBehavior = function(initialValue) {
  86       var source;
  87       source = this;
  88       return this.buildBehavior(initialValue, function() {
  89         var _this = this;
  90         return this.subscribe(source, 'value', function() {
  91           var metadata, value;
  92           value = arguments[0], metadata = 2 <= arguments.length ? __slice.call(arguments, 1) : [];
  93           return _this.emitValue.apply(_this, [value].concat(__slice.call(metadata)));
  94         });
  95       });
  96     };
  97
  98     Signal.prototype.changes = function() {
  99       return this;
 100     };
 101
 102     Signal.prototype.injectMetadata = function(fn) {
 103       var source;
 104       source = this;
 105       return new this.constructor(function() {
 106         var _this = this;
 107         return this.subscribe(source, 'value', function(value, metadata) {
 108           var k, newMetadata, v;
 109           newMetadata = fn(value, metadata);
 110           for (k in newMetadata) {
 111             v = newMetadata[k];
 112             metadata[k] = v;
 113           }
 114           return _this.emitValue(value, metadata);
 115         });
 116       });
 117     };
 118
 119     Signal.prototype.filter = function(predicate) {
 120       var source;
 121       source = this;
 122       return new this.constructor(function() {
 123         var _this = this;
 124         return this.subscribe(source, 'value', function() {
 125           var metadata, value;
 126           value = arguments[0], metadata = 2 <= arguments.length ? __slice.call(arguments, 1) : [];
 127           if (predicate.call(value, value)) {
 128             return _this.emitValue.apply(_this, [value].concat(__slice.call(metadata)));
 129           }
 130         });
 131       });
 132     };
 133
 134     Signal.prototype.filterDefined = function() {
 135       return this.filter(function(value) {
 136         return value != null;
 137       });
 138     };
 139
 140     Signal.prototype.map = function(fn) {
 141       var property, source;
 142       if (typeof fn === 'string') {
 143         property = fn;
 144         fn = function(value) {
 145           return value != null ? value[property] : void 0;
 146         };
 147       }
 148       source = this;
 149       return new this.constructor(function() {
 150         var _this = this;
 151         return this.subscribe(source, 'value', function() {
 152           var metadata, value;
 153           value = arguments[0], metadata = 2 <= arguments.length ? __slice.call(arguments, 1) : [];
 154           return _this.emitValue.apply(_this, [fn.call(value, value)].concat(__slice.call(metadata)));
 155         });
 156       });
 157     };
 158
 159     Signal.prototype["switch"] = function(fn) {
 160       var source;
 161       source = this.map(fn);
 162       return new this.constructor(function() {
 163         var currentSignal,
 164           _this = this;
 165         currentSignal = null;
 166         return this.subscribe(source, 'value', function(newSignal, outerMetadata) {
 167           if (currentSignal != null) {
 168             _this.unsubscribe(currentSignal);
 169           }
 170           currentSignal = newSignal;
 171           if (currentSignal != null) {
 172             return _this.subscribe(currentSignal, 'value', function(value, innerMetadata) {
 173               return _this.emitValue(value, innerMetadata);
 174             });
 175           } else {
 176             return _this.emitValue(void 0, outerMetadata);
 177           }
 178         });
 179       });
 180     };
 181
 182     Signal.prototype.skipUntil = function(predicateOrTargetValue) {
 183       var doneSkipping, predicate, targetValue;
 184       if (typeof predicateOrTargetValue !== 'function') {
 185         targetValue = predicateOrTargetValue;
 186         return this.skipUntil(function(value) {
 187           return isEqual(value, targetValue);
 188         });
 189       }
 190       predicate = predicateOrTargetValue;
 191       doneSkipping = false;
 192       return this.filter(function(value) {
 193         if (doneSkipping) {
 194           return true;
 195         }
 196         if (predicate(value)) {
 197           return doneSkipping = true;
 198         } else {
 199           return false;
 200         }
 201       });
 202     };
 203
 204     Signal.prototype.scan = function(initialValue, fn) {
 205       var source;
 206       source = this;
 207       return this.buildBehavior(initialValue, function() {
 208         var oldValue,
 209           _this = this;
 210         oldValue = initialValue;
 211         return this.subscribe(source, 'value', function() {
 212           var metadata, newValue;
 213           newValue = arguments[0], metadata = 2 <= arguments.length ? __slice.call(arguments, 1) : [];
 214           return _this.emitValue.apply(_this, [(oldValue = fn(oldValue, newValue))].concat(__slice.call(metadata)));
 215         });
 216       });
 217     };
 218
 219     Signal.prototype.diff = function(initialValue, fn) {
 220       var source;
 221       source = this;
 222       return this.buildBehavior(function() {
 223         var oldValue,
 224           _this = this;
 225         oldValue = initialValue;
 226         return this.subscribe(source, 'value', function() {
 227           var fnOldValue, metadata, newValue;
 228           newValue = arguments[0], metadata = 2 <= arguments.length ? __slice.call(arguments, 1) : [];
 229           fnOldValue = oldValue;
 230           oldValue = newValue;
 231           return _this.emitValue.apply(_this, [fn(fnOldValue, newValue)].concat(__slice.call(metadata)));
 232         });
 233       });
 234     };
 235
 236     Signal.prototype.distinctUntilChanged = function() {
 237       var source;
 238       source = this;
 239       return new this.constructor(function() {
 240         var oldValue, receivedValue,
 241           _this = this;
 242         receivedValue = false;
 243         oldValue = void 0;
 244         return this.subscribe(source, 'value', function() {
 245           var metadata, newValue;
 246           newValue = arguments[0], metadata = 2 <= arguments.length ? __slice.call(arguments, 1) : [];
 247           if (receivedValue) {
 248             if (isEqual(oldValue, newValue)) {
 249               return oldValue = newValue;
 250             } else {
 251               oldValue = newValue;
 252               return _this.emitValue.apply(_this, [newValue].concat(__slice.call(metadata)));
 253             }
 254           } else {
 255             receivedValue = true;
 256             oldValue = newValue;
 257             return _this.emitValue.apply(_this, [newValue].concat(__slice.call(metadata)));
 258           }
 259         });
 260       });
 261     };
 262
 263     Signal.prototype.equals = function(expected) {
 264       return this.map(function(actual) {
 265         return isEqual(actual, expected);
 266       }).distinctUntilChanged();
 267     };
 268
 269     Signal.prototype.isDefined = function() {
 270       return this.map(function(value) {
 271         return value != null;
 272       }).distinctUntilChanged();
 273     };
 274
 275     Signal.prototype.buildBehavior = function() {
 276       var args;
 277       args = 1 <= arguments.length ? __slice.call(arguments, 0) : [];
 278       if (Behavior == null) {
 279         Behavior = require('./behavior');
 280       }
 281       return (function(func, args, ctor) {
 282         ctor.prototype = func.prototype;
 283         var child = new ctor, result = func.apply(child, args);
 284         return Object(result) === result ? result : child;
 285       })(Behavior, args, function(){});
 286     };
 287
 288     return Signal;
 289
 290   })(Emitter);
 291
 292 }).call(this);