VJET/ANVILS

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Introducing VJET ANVILS

(Formerly known as VJET Type libraries)

Authoring - give you great code assist for the right javascript scope

Navigation - help you navigate the code base based on call hierarchy, references, etc.

Validation - provide semantic validation

Instruction - Helps with inline documentation

Libraries - Packaged as an Eclipse project just import and depend on.

VJET ANVILs provide a way to work with 3rd party Javascript libraries without requiring an Eclipse plugin because the ANVILS are described with javascript.

The idea behind the "ANVIL" is to create definitions which describe other JavaScript libraries. JavaScript is a huge area today thanks to Client and Server-side libraries such as jQuery and Node.js.

ANVIL "descriptions" are defined in a structured definition format called vjo.js. vjo.js is JavaScript itself (which is kind of nice - JavaScript describing other JavaScript).

We can think of the vjo.js as being similar to Java Interfaces and Class declarations. We can "describe" the coding contracts only but no their implementation. The implementation is always the real runtime library that would physically be included in your webpage like jquery (<script src="http://code.jquery.com/jquery-1.9.1.min.js";></script>) or server-side Node module being used via require(...).

The Type Library is read in by the Eclipse IDE and provides the necessary information for it to provide authoring assistance and validations. Authoring assistance would be things like type completion and proposals which are concepts we generally enjoy with typed languages like Java.

Also, those definitions help VJET do validation on your code as well. For example your function takes a String and Number argument but someone passed in an Array or Date. In raw JavaScript this is just tough luck and bad things happen at runtime. With VJET, this scenario is caught and flagged as an error for the developer to correct.

JavaScript is a simple language on the surface and provides very limited types (Object, Function, Array, Date, Boolean, String, Number and RegExp) only. However, JavaScript can create very complex functions and types that benefit from more type support and that's where VJET comes into play.