Haml weppy extension

weppy-Haml provides a Haml like syntax for templates. This is not a template engine but a compiler which converts haml files to html weppy templates.

Haml-like syntax

So, how an haml template will look like? Let's say you have this html template in your application:

{{extend 'layout.html'}}

<div class='row'>
    <div id='posts' class='posts'>
    {{for post in posts:}}
        <div class='col-md-4'>
            {{if post.image:}}
            <img src='{{=post.image}}' class='post-image' />
            <h3 class='post-title'>

Then the same template in haml syntax will be like this:

- extend 'layout.html'

    - for post in posts
            - if post.image
                %img.post-image{src: '{{=post.image}}'}
                = post.title
                = post.description

Here is a short list of weppy-Haml pros vs the default html templating system:

  • Less code to write
  • Your code will be more human readable
  • You don't have to write the pass instructions, just to correctly indent your code

So, you still gonna use html? :)


You can install weppy-Haml using pip:

pip install weppy-Haml

And add it to your weppy application:

from weppy_haml import Haml



weppy-Haml has 2 configuration options:

parameter default value description
set_as_default False set the default extension for templates to haml
auto_reload False check for changes in template files and reload them

If you only use haml templates, you should set the set_as_default parameter to True:

app.config.Haml.set_as_default = True

so when you expose a function from your application without explicitly pass the template

def myfunction():
    # some awesome code

weppy will look at the haml file (in this case myfunction.haml) insted of the html one.

When you set configuration values for the extension, ensure to do that before adding the extension to your application.

Auto reloading haml templates

The auto reload feature of Haml extension works in the same way of weppy caching system for templates – introduced since v0.3 – so it's automatically enabled when your application is in debug mode, ignoring the configuration value.

Depending on your needs – and remembering that the auto-reload feature might affect your application performance in production – you can set the auto_reload parameter to True, but it will work only if you set the templates_auto_reload parameter of your application configuration to True as well:

app.config.templates_auto_reload = True
app.config.Haml.auto_reload = True

Suggested .gitignore

If you're using git version control system for your application, you'd better add to your .gitignore file:


so you won't track the generated html files from the haml ones.