Lesson 7: Troubleshooting

Thousands of YAML files have been shared with us. These are the most common issues grouped into categories:


  • Valid indentation but invalid outcome. For example, a map key belonging to the wrong map due to an indentation issue.
  • Using wrong (and invisible to the eye) characters like a tab instead of a space.

Solution: use spaces, and two space increments are standard for levels of indentation for YAML (even though others space increments are valid). Two spaces are most recognized by users.

Missed space after colon

  • Map keys need a colon followed by a space

Solution: add the space

Not escaped characters

Not escaping characters including :, -, and #.

Solution: use block scalars or quotes.

Character set

YAML processors should support UTF-8, UTF-16, and UTF-32.

Be wary if you're using anything else.