Comments
Using the standard {% comment %} tag you can mark a block of template text as a comment. Python Liquid does not parse or render anything between {% comment %} and {% endcomment %}.
{% comment %} Determine if the current product is on sale. {% endcomment %}
{% liquid
if product.was_price
assign on_sale = true
else
comment was_price is undefined
endcomment
assign on_sale = false
endif
%}
Python Liquid will raise a LiquidSyntaxError if it finds the string {% endcomment %} inside a comment block. Ruby Liquid, on the other hand, will successfully parse fully-formed nested comment blocks, but will fail to parse a comment block containing either a {% comment %} or {% endcomment %} on its own.
Similarly, with the inline comment tag added in Python Liquid version 1.2.0, one or more lines can be commented out in a single inline tag.
Both the traditional comment block and the newer inline comment tag suffer from problems when commenting out other liquid tags.
Alternative Comment Syntax
New in version 1.1.0
Python Liquid offers an alternative, non-standard template comment syntax. When enabled, anything between {# and #} will be treated as a comment. It is disabled by default. Enable it using the template_comments argument to liquid.Environment or liquid.Template.
This alternative comment syntax is non-standard. If you choose to use it in your templates, those templates are unlikely to render correctly with other implementations of Liquid.
from liquid import Environment
env = Environment(template_comments=True)
Because this comment syntax is not implemented as a tag, there are no issues commenting out arbitrary chunks of Liquid.
{# note: comment this out for now
{% for x in (1..5) %}
{{ x }}
{% endfor %}
#}
Inside {% liquid %} tags any line starting with a hash is considered a comment.
{% liquid
# greetings
echo 'Hello, World!'
# Multi line
# comment
%}