A toy templating engine. Accompanying blog post: http://alexmic.net/building-a-template-engine/.

I just wanted to learn how to write a templating engine. It's not feature-complete or production-ready. It's a playground and it will be a work in progress.

There are two types of tags, blocks and variables.

<div>{{my_var}}</div>

There are three types of blocks – if, each and call.

{% each items %}
    <div>{{it}}</div>
{% end %}

{% each [1,2,3] %}
    <div>{{it}}</div>
{% end %}

it references the current item in the iteration and it is scoped to this item's attributes. To access attributes of the parent context use ... For example:

{% each items %}
    <div>{{..name}}</div><div>{{it}}</div>
{% end %}

Supported operators are: >, >=, <, <=, ==, !=. You can also use conditionals with things that evaluate to truth.

{% if num > 5 %}
    <div>more</div>
{% else %}
    <div>less or equal</div>
{% end %}

{% if items %}
    <div>we have items</div>
{% end %}

Callables can get passed positional or keyword arguments.

<div class='date'>{% call prettify date_created %}</div>
<div>{% call log 'here' verbosity='debug' %}</div>

Using benchmarks.py and the templates files in templates/ here are the results:

microtemplates => run 1000 times, took 0.58 ms
django => run 1000 times, took 1.39 ms
jinja2 => run 1000 times, took 7.68 ms