Element Tags and C#

.shade files use an offside-rule format, like Python, Jade, or Haml, which means that indentation determines structure. .shade templates can contain a mix of element tags and C# code. The concept of element tags in a .shade file makes sense when you consider that .shade files are templates processed by the Spark view engine into a dynamically generated class. Originally, these classes would have been used to generate a response in a web site (think Razor and .cshtml files); Sake repurposes Spark to process .shade template files into classes that run a build.

Working with Element Tags

Sake comes with a standard set of element tags, like exec and log, and you can also create your own Custom Element Tags. A .shade file will also use element tags from Spark, like use and macro. See the Spark elements reference for more information.

Note

I have not tried to use all of the Spark elements in a Sake build file, and some may not make sense to use in a build file, or may not work as described in the Spark documentation.

The following .shade file illustrates the basics of working with element tags and can be run using the build.cmd file from Getting Started. Sake requires at least one target, so we define one here named #default. Targets are explained in detail later in the documentation.

Interesting things to note:

• Strings are delimited with single or double quotes.
• Element tags that are not indented run before targets.

-// example of a single-line comment

-/* 
   example of a 
   multi-line comment
*/

log warn="This executes first."

#default
   log info='Hello world'

log warn="This also executes before the target."

Running the file above produces the following output:

warn: This executes first.
warn: This also executes before the target.
info: Hello world

Working with C#

C# code can be used as a code block, delimited with @{ and }:

@{
   var message = "Hello world!";
   Log.Info(message);
}

C# can also appear in element tags, delimited with ${ and }:

log info="The current date and time is ${DateTime.Now.ToString()}."

Note

Version 0.2.2 of Sake targets .NET 4.0, which corresponds to C# 4.

String Delimiters

As with element tags, strings in C# code can be delimited using either single or double quotes. This raises the interesting problem of working with char variables in C#. For example, the following code will generate an exception in a .shade file:

var tokens = "a,b,c".Split(',');

The ',' argument is treated as a string, and an exception will be thrown because Split expects a char. To work around this, cast to char:

var tokens = "a,b,c".Split((char)',');

Namespaces

The use element is analogous to the using directive in C#. In the example below, Console and Directory do not need to be fully qualified because the System and System.IO namespaces are specified by the use elements:

use namespace="System"
use namespace="System.IO"

#default
   @{
      Console.WriteLine(Directory.GetCurrentDirectory());
   }

The following .shade file shows the basics of working with C# in Sake, and also how you can work with both C# and tags in the same build file.

use namespace="System"

#default

   @{
      var now = DateTime.Now;

      Console.WriteLine("Hello world using C#!");
   }

   log info="Hello world using tags!  It is ${now.ToString()}"

This produces the following output:

>build.cmd
Hello world using C#!
info: Hello world using tags!  It is 11/14/2015 12:24:29 PM