Shopify: Why does Liquid sometimes use {%- instead of {%?

Question

I've been looking through the code of the default theme, and I've noticed that sometimes they use the {% tag to indicate Liquid code (as per the documentation), but other times they use {%-.

For example:

  {% case section.settings.image_size %}
    {% when 'small' %}
      {%- assign product_image_width = 'medium-up--one-third' -%}
      {%- assign product_description_width = 'medium-up--two-thirds' -%}

I cannot find a single example of {%- in the Liquid documentation, either on the Shopify site, or on GitHub, but I've seen other people use it on the Shopify forums, too.

What does the addition of a - signify?

Answer 1

The hyphens are a new syntax option that you can use to suppress blank lines that would otherwise show up in the source. You can learn more about this here: https://shopify.github.io/liquid/basics/whitespace/