underscore.js

I've got a short search form that a user fills out. There will be multiple search queries that will go into MongoDB: The form creates a variable called searchParams that may look like this: var searchParams = { city: "Springfield", bedrooms: 3, bathrooms: 2 }; I then have a function that takes the searchParams as an argument and queries Mongo using it: var searchListings = function(searchParams){ return db.MyListings.find(searchParams).fetch(); } db.MyListings.find( {city: "Springfield", bedrooms: 3, bathrooms: 2} ).fetch(); This is all well and good for a complete searchParams object, but if

I'm currently using underscore.js for templating in a project, templates are stored in script tags with a type of text/template and loaded by id. I'm wondering if it's possible to continue to use the same system, but move the templates to a separate file? The only way I can think about doing this is declaring the templates as global vars in a separate file, but that seems ugly. Note: I don't want to use Jammit or some other build system for mashing everything together into a single file at deployment time, wondering if there's another solution. I personally use RequireJS to load my templates

Never seen the .apply method before. Can someone explains to me what it does? This is taken from http://addyosmani.github.com/backbone-fundamentals/ var app = app || {}; var TodoList = Backbone.Collection.extend({ model: app.Todo, localStorage: new Backbone.LocalStorage(’todos-backbone’), completed: function() { return this.filter(function( todo ) { return todo.get(’completed’); }); }, remaining: function() { return this.without.apply( this, this.completed() ); }, nextOrder: function() { if ( !this.length ) { return 1; } return this.last().get(’order’) + 1; }, comparator: function( todo ) {

I want to do something like this: <script id="tmpl-books" type="text/template"> <ul> <% for (var i = 0; i < books.length; i++) { %> <% var book = books[i]; %> <li> <em><%= book.title %></em> by <%= book.author %> </li> <% } %> </ul> </script> in my code, but I am using JSP so I have to use the {{ }} notation, but when I do this {{ for(var... }} does not work. <script id="tmpl-books" type="text/template"> <ul> {{ for (var i = 0; i < books.length; i++) { }} <% var book = books[i]; %> <li> <em>{{= book.title }}</em> by {{ book.author }} </li> {{ } }} </ul> </script> How can I achieve this? mu is

我有一个JavaScript对象，是否有内置的或公认的最佳实践方法来获取此对象的长度？ const myObject = new Object(); myObject["firstname"] = "Gareth"; myObject["lastname"] = "Simpson"; myObject["age"] = 21; #1楼 更新 ：如果您使用的是 Underscore.js （建议使用，它是轻量级的！），那么您可以 _.size({one : 1, two : 2, three : 3}); => 3 如果不是 ，并且您不想由于任何原因弄乱Object属性，并且已经在使用jQuery，那么同样可以访问一个插件： $.assocArraySize = function(obj) { // http://stackoverflow.com/a/6700/11236 var size = 0, key; for (key in obj) { if (obj.hasOwnProperty(key)) size++; } return size; }; #2楼 以下是James Coglan在CoffeeScript中针对那些放弃了直接JavaScript的人的答案：) Object.size = (obj) -> size = 0 size++ for own key of

I have a few tabs on my page, whose contents (consisting of many SetView contained by SetListView ) are loaded using Backbone.js whenever its tabs is being clicked on. Problem:: When the user switches from a tab to a previously loaded/viewed tabbed, the contents load again and append to the previously loaded content in SetListView . I can get it to clear the previously loaded contents before loading it again, but it seems to be less than optimal to keep loading the same content. Is it possible to make Backbone.js store existing content for a tab and not load it multiple times when switching

The title is a little bit confusing but I essentially want to convert this: [ {a: 1, b: 2, c:3}, {a: 4, b: 5, c:6}, {a: 7, b: 8, c:9} ] into: { a: [1,4,7], b: [2,5,8], c: [3,6,9] } using lodash (requirement). Any ideas??? Here's a solution using lodash that maps across the keys and plucks the values for each key from the data before finally using _.zipOobject to build the result. var keys = _.keys(data[0]); var result = _.zipObject(keys, _.map(keys, key => _.map(data, key))); Look for _.map here input = [ {a: 1, b: 2, c:3}, {a: 4, b: 5, c:6}, {a: 7, b: 8, c:9} ]; output = {}; _.map(input,

For education purposes, I was trying to re-create Underscore.js's _.reduce() method. While I was able to do this in an explicit style using for loops. But this is far from ideal because it mutates the original list that was supplied as an argument, which is dangerous. I also realized that creating such method using functional programming style is harder, since it is not possible to explicitly set i value for looping. // Explicit style var reduce = function(list, iteratee, initial) { if (Array.isArray(list)) { var start; if (arguments.length === 3) { start = initial; for (var i = 0; i < list