Slide 78
Slide 78 text
(function() {
var wrap,
__slice = [].slice;
wrap = function(listener, toDo, invokeAlways, isDefined) {
return _.wrap(toDo, function() {
var args, originalFn, value, valueIsDefined;
originalFn = arguments[0], value = arguments[1], args = 3 <= arguments.length ? __slice.call(arguments, 2) : [];
valueIsDefined = isDefined(value);
if (!invokeAlways && !valueIsDefined) {
return;
}
originalFn.call.apply(originalFn, [this, value].concat(__slice.call(args)));
if (valueIsDefined) {
return listener.cleanup();
}
});
};
angular.module('ngWatchWhen', []).constant('ngWatchWhenRegEx', /^\:\:([^\:]+)(\:\:[^\:]+)$/).value('ngWatchWhenCloneExpression', function(getter) {
var clone;
clone = function() {
return getter.apply(this, arguments);
};
return _.merge(clone, getter);
}).config(function($provide) {
return $provide.decorator('$parse', function($delegate, ngWatchWhenRegEx, ngWatchWhenDelegateFactory, ngWatchWhenCloneExpression) {
return _.wrap($delegate, function($parse, exp, interceptor) {
var args, match, onceExp, onceStr, whenExp, whenStr;
if (angular.isString(exp) && (match = exp.match(ngWatchWhenRegEx))) {
exp = match[0], whenStr = match[1], onceStr = match[2];
whenExp = $parse.apply(this, [whenStr]);
onceExp = ngWatchWhenCloneExpression($parse.apply(this, [onceStr, interceptor]));
onceExp.$$watchDelegate = ngWatchWhenDelegateFactory(whenExp, onceExp);
return onceExp;
} else {
args = [exp];
if (interceptor != null) {
args.push(interceptor);
}
return $parse.apply(this, args);
}
});
});
}).value('ngWatchWhenDelegateFactory', function(whenExp, onceExp) {
return _.wrap(onceExp.$$watchDelegate, function(originalWatchDelegate, scope, listener, objectEquality, parsedExpression) {
var onceWatch, registerOnceWatch, whenWatch;
onceWatch = null;
registerOnceWatch = function() {
onceWatch = {};
onceWatch.deregister = originalWatchDelegate.call(this, scope, listener, objectEquality, parsedExpression);
return onceWatch.watcher = _.first(scope.$$watchers);
};
registerOnceWatch();
whenWatch = scope.$watch(whenExp, function() {
if (!_.contains(scope.$$watchers, onceWatch.watcher)) {
return registerOnceWatch();
}
});
return function() {
whenWatch();
if (_.contains(scope.$$watchers, onceWatch.watcher)) {
return onceWatch.deregister();
}
};
});
});
}).call(this);