What does this - in jinja2 template engine do?

2024/11/21 0:33:27

I am learning jinja2 because Google App Engine recommends it.

I found this example on Wikipedia: http://en.wikipedia.org/wiki/Jinja_%28template_engine%29

  {%- for item in item_list %}{{ item }}{% if not loop.last %},{% endif %}{%- endfor %}

What is the "-" in "{%- for"?

Also, where can I find jinja2 examples (better with Google App Engine)?

Thanks a lot!

Answer

It suppresses extra vertical spacing, commonly used when you don't want excessive spacing between elements you're looping through.

If you put an minus sign (-) to the start or end of a block (forexample a for tag), a comment or variable expression you can removethe whitespaces after or before that block

See: http://jinja.pocoo.org/docs/templates/#whitespace-control

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