Filter blocks

Filter blocks provide a way to include non-template text inside the template script. Unlike the template syntax which follow strict indentation rules, text inside a filter block are completely exempted from Tayra-Template-Language syntax.

A filter block should be opened in a new-line prefixed by any number of white-spaces, and this opening newline must always be confirmant to the template’s indentation rules. Any number of text-lines can follow the opening-line and the text-lines can have their own syntax dictated by corresponding filter-blocks.

A filter block is closed by a newline prefixed by any number of white-spaces similar to the opening line.

Here is an example,

:py:
  a = 'empty'
  def insideroot_butglobal():
    return '<div> insideroot_butglobal </div>'
:py:

:py:
  b = '<div> insideroot_insidebody </div>'
:py:

${ a } ${ insideroot_butglobal() }
${ b }

@def func() :
  <div> hello world

The above example demonstrates a filter-block called py implemented by an tayra.interfaces.ITayraFilterBlock plugin called py. Filter blocks are handled by plugins and the correct plugin to handle the filter block is choosen based on the opening line’s filter-block name.

Plugins handling filter-blocks, directly take part in compilation phases of the template script and can even generate stack machine instructions directly. We believe this open ended design will lead us to more interesting language features, features though implemented / extended using plugin can be tightly integrated with the language.

py filter block

The filter block allows developers to include blocks of python code inside the template script. Note that the syntax of text inside this filter block should follow python programming syntax.

Code block defined inside a template-function or template-method will be local to the scope of the function or method.

Globally defined code blocks will be interpreted in the global scope and the side effects created by the code block will be available to all function and methods defined in the template script.

To learn how to extend filter blocks with a plugin, refer to ITayraFilterBlock section in this article.