Jinja List Comprehension

Practice writing list comprehension, using Jinja, to create a new list from existing list data

Module Overview

💡 List comprehension (a special enhancement to "Rewst-flavored Jinja"!) allows you to create a new list from an existing one in a simplified way, without needing to end the code with {% endfor %}. It consists of three parts:

1. Output – What do you want in your new list?

2. For Loop – How do you loop through data in the original list?

3. Condition (Optional) – Do you need to filter items to include in your new list?

Here's the basic structure:

{{ [ output for output in CTX.list if condition ]}}

Video (3:16 Minutes)

Additional Tips

• Use dot notation in the output to specify parts of each item.

• The condition (typically, an "if" statement) is optional and filters based on criteria like "if the color is not red."

• If you want to turn the list into a string, apply the "join" filter. You'll find an example of this in the "Lunch Menu" exercises for this lesson.

For a few examples, refer to the Jinja List Comprehension Examples module.

Action Items

Practice the list comprehension exercises included in the "Lunch Menu" data set: Lesson Resources

Navigation

Go to the previous module:

Basic Jinja Syntax and Filters

Go to the next module:

Jinja List Comprehension Examples ("Them Apples")