A parser for a subset of the Jade/PugJS template engine. Built for .NET core, and intended for use with NancyFX.

KJade has no external dependencies; the lexer and parser were written from scratch with regex. HTML/XML building is done at the end, and KJade provides the ICompiler interface allowing anyone to implement a compiler to a language other than XML from the KJade AST, a simple tree.

This parser is an experimental implementation of some of the Jade syntax. It works by reading through the code, lexing it into tokens, and building an AST from the tokens.

Finally, an extensible class is used to allow generation of HTML/XML from the AST. KJade is completely written in C#, and is built for the .NET core platform.

KJade is not intended to be able to handle all Jade syntax; its aim is instead to provide a concise templating experience similar to that of Jade/PugJS, but with C#/.NET instead of JS.

KJade syntax is a subset of Jade syntax. While Jade often has a number of different syntaxes that will evaluate to the same result, KJade omits such syntactic forms.

For example, Jade supports multiline values for elements with both | and a . after the element name. KJade only supports the . method, and treats | as part of the element value.

A hierarchy of elements is built based on indentation level. Two nodes on the same indentation level end up in the same nesting level in XML.

Here's a short document demonstrating some of the syntax:

html
    head
        title Test Page
    body
        div#intro(a1="val1",a2="val2")
            h1 This is a KJade test!
            p easy
            p.friendly easier!
            p.
                Free form
                paragraph!
            h1 Hello, #{model.Name}!
        .lol#infer-node-type
        .btn.btn-default.btn-cool.btn-amazing
        div#some-id.another-class
            h2 Some more information
        div.some-class.some-other-class
            h2 Finally
        div(some-attr="some value")
            p This div is really unique, using paren notation!

Additionally, block comments are not supported, only single line comments with // are supported. Each comment must be on its own line. Indentation before the // is ignored.

• KJade is very indentation sensitive!
• KJade does NOT support single quotes (') for enclosing attribute values.

KJade's variable replacement works differently than Jade's: The Compile method of JadeCompiler has an optional argument specifying a model, which can be any object.

For example, let our model be an object like this: { Name = "Bob" } Then, in the value of a KJade block, Hello, #{model.Name} would evaluate to Hello, Bob.

Additionally, putting a ! before the # will tell KJade to automatically HTML-encode the value of the property of the model.

You can specify data that will only be shown if a property of the model evaluates to not null or true. Otherwise, the data will be hidden. This is useful for error messages. The syntax is as follows:

@if model.InputHasError
Your input has an error.
@endif

You can expand data with Enumerables. If you pass in a property that implements IEnumerable, KJade will expand the code within, replacing {$element} with the string representation of the current element. You can use this to render lists or other repeating structures easily.

@enumerable model.SomeEnumerable
li {$element}
@endenumerable

KJadeViewEngine is a NancyFx plugin that allows you to use KJade in your Nancy web applications. These features are only available when using the view engine.

In the NancyFx View Engine plugin, you can import other views with @import [view name]. For example, the following will import the header view:

@import Header

Partials are very similar to imports, except that they specify an alternate model. The syntax is as follows:

@partial [view name];[model]

For example:

@partial Components/PartialTest;model.PTestModel

This will import Components/PartialTest and evaluate it with the model model.PTestModel, where model is the model of the current view.