Properties are not the same as variables. Variables are local to a thread; properties are common to all threads, and need to be referenced using the With the suggestion that the preceding statement be terminated with a semicolon. Some suggest instead the use of leading semicolons on lines starting with '(' or. The code in the post DOES NOT WORK if the url has php get parameters AND # sign at the end of the variable value you are trying to get!!! Still having problems? Try reading through the previous SWFObject posts Cross-platform text editor for code and any kind of text file. Supports syntax highlighting, completion, projects and plugins. Less extends CSS with dynamic behavior such as variables, mixins, operations and functions. Less runs on both the server-side (with Node.js and Rhino) or client-side. Sass (Syntactically Awesome StyleSheets) Table of contents :toc; Sass is an extension of CSS that adds power and elegance to the basic language. It allows you to use. This specification provides an API for representing file objects in web applications, as well as programmatically selecting them and accessing their data. Getting the Code The code we’ll be using in this book is hosted in a repository on Github. You can download a.zip or.tar file of the code, then uncompress.Require. JS APIRequire. JS takes a different approach to script loading than traditional < script> tags. As part of that, it encourages using module IDs instead of URLs for script tags. Require. JS loads all code relative to a base. Url. The base. Url is normally set to the same directory as the script used in a data- main attribute for the top level script to load for a page. The data- main attribute is a special attribute that require. This example will end up with a base. Url of scripts: < !- -This sets the base. Url to the . If there is no explicit config and data- main is not used, then the default base. Url is the directory that contains the HTML page running Require. JS. Require. JS also assumes by default that all dependencies are scripts, so it does not expect to see a trailing . Require. JS will automatically add it when translating the module ID to a path. With the paths config, you can set. All of these capabilities allow you to use smaller strings for scripts as compared to traditional < script> tags. There may be times when you do want to reference a script directly and not conform to the . If a module ID has one of the following characteristics, the ID will not be passed through the . By doing so, it gives you more flexibility in renaming and configuring the paths to different locations for optimization builds. Similarly, to avoid a bunch of configuration, it is best to avoid deep folder hierarchies for scripts, and instead either keep all the scripts in base. Url, or if you want to separate your library/vendor- supplied code from your app code, use a directory layout like this: www/. It is recommended to store that version info in a separate text file if you want to track it, or if you use a tool like volo, it will stamp the package. This allows you to have the very minimal configuration instead of having to put an entry in the . For instance, configure . However, you may need to use some traditional/legacy . For those, you can use the shim config. To properly express their dependencies. If you do not express the dependencies, you will likely get loading errors since Require. JS loads scripts asynchronously and out of order for speed. The data- main attribute is a special attribute that require. Note: the script tag require. This means that you cannot assume that the load and execution of your data- main script will finish prior to other scripts referenced later in the same page. For example, this arrangement will fail randomly when the require. When that happens, require. For pages that want to do inline require() calls, it is best to nest those inside a require() call for the configuration: < script src=. It can explicitly list its dependencies and get a handle on those dependencies without needing to refer to global objects, but instead receive the dependencies as arguments to the function that defines the module. Modules in Require. JS are an extension of the Module Pattern, with the benefit of not needing globals to refer to other modules. The Require. JS syntax for modules allows them to be loaded as fast as possible, even out of order, but evaluated in the correct dependency order, and since global variables are not created, it makes it possible to load multiple versions of a module in a page.(If you are familiar with or are using Common. JS modules, then please also see Common. JS Notes for information on how the Require. JS module format maps to Common. JS modules). There should only be one module definition per file on disk. The modules can be grouped into optimized bundles by the optimization tool. If the module does not have any dependencies, and it is just a collection of name/value pairs, then just pass an object literal to define(): //Inside file my/shirt. The function will be called to define the module once all dependencies have loaded. The function should return an object that defines the module. The dependencies will be passed to the definition function as function arguments, listed in the same order as the order in the dependency array: //my/shirt. It depends on my/cart and my/inventory. On disk, the files are structured like this: my/cart. The function call above specifies two arguments, . These are the modules represented by the . Also, the order of the function arguments should match the order of the dependencies. The return object from the function call defines the . By defining modules in this way, . Any valid return value from a function is allowed. Here is a module that returns a function as its module definition: //A module definition inside foo/title. It uses. //my/cart and my/inventory modules from before. You can use the simplified Common. JS wrapper for those cases: define(function(require, exports, module) . This does not work on some devices like the PS3 and some older Opera mobile browsers. Use the optimizer to pull out the dependencies in the array format for use on those devices. More information is available on the Common. JS page, and in the . You can explicitly name modules yourself, but it makes the modules less portable - - if you move the file to another directory you will need to change the name. It is normally best to avoid coding in a name for the module and just let the optimization tool burn in the module names. The optimization tool needs to add the names so that more than one module can be bundled in a file, to allow for faster loading in the browser. One module per file.: Only one module should be defined per Java. Script file, given the nature of the module name- to- file- path lookup algorithm. You shoud only use the optimization tool to group multiple modules into optimized files. Relative module names inside define(): For require(. So for relative name references, those are resolved relative to the module name making the reference, then that module name, or ID, is converted to a path if needs to be loaded. Example code for a 'compute' package that has a 'main' and 'extras' modules in it: * lib/. When it asks for './extras', that is resolved relative to 'compute', so 'compute/./extras', which normalizes to just 'extras'. Since there is no paths config for that module name, the path generated will be for 'lib/extras. For this case, packages config is a better option, since it allows setting the main module up as 'compute', but internally the loader will store the module with the ID of 'compute/main' so that the relative reference for './extras' works. Another option is to construct a module at lib/compute. To do so, ask for . If using a relative path, like './module/name', those only work inside define. If you define a circular dependency (. Circular dependencies are rare, and usually a sign that you might want to rethink the design. However, sometimes they are needed, and in that case, use require() as specified above. If you are familiar with Common. JS modules, you could instead use exports to create an empty object for the module that is available immediately for reference by other modules. By doing this on both sides of a circular dependency, you can then safely hold on to the the other module. This only works if each module is exporting an object for the module value, not a function: //Inside b. However, we cannot use. However, we cannot use. It works across domains and it is an established approach to calling services that just require an HTTP GET via a script tag. To use a JSONP service in Require. JS, specify . This means you can get the value of a JSONP URL as if it was a module definition. Here is an example that calls a JSONP API endpoint. In this example, the JSONP callback parameter is called . If the JSONP service times out, it means other modules you define via define() may not get executed, so the error handling is not robust. Only JSONP return values that are JSON objects are supported. A JSONP response that is an array, a string or a number will not work. This functionality should not be used for long- polling JSONP connections - - APIs that deal with real time streaming. Those kinds of APIs should do more script cleanup after receiving each response, and Require. JS will only fetch a JSONP URL once - - subsequent uses of the same URL as a dependency in a require() or define() call will get a cached value. Errors in loading a JSONP service are normally surfaced via timeouts for the service, since script tag loading does not give much detail into network problems. To detect errors, you can override requirejs. Error() to get errors. There is more information in the Handling Errors section. There is a global function, requirejs. It will reset the. However, it will not remove the module from other modules that are already defined and got a. So it is really only useful to use in. See the errback section for an example. If you want to do more sophisticated dependency graph analysis for undefining work, the semi- private. Resource. Load API may be helpful. Require. JS loads each dependency as a script tag, using head. Child(). Require. JS waits for all dependencies to load, figures out the right order in which to call the functions that define the modules, then calls the module definition functions once the dependencies for those functions have been called. Note that the dependencies for a given module definition function could be called in any order, due to their sub- dependency relationships and network load order. Using Require. JS in a server- side Java. Script environment that has synchronous loading should be as easy as redefining require. The build system does this, the require. Patch. js. In the future, this code may be pulled into the require/ directory as an optional module that you can load in your env to get the right load behavior based on the host environment. When using require() in the top- level HTML page (or top- level script file that does not define a module), a configuration object can be passed as the first option: < script src=. Note that this function could. Avoid other entry point scripts which wrongly assume that data- main and its require.
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