Whitespace in Tag

A YAML tag contains whitespace around a component.

Q-1-25 — Whitespace in Tag

A YAML tag contains whitespace around a component.

What this means

Quarto’s configuration tags are written in compact form, with no spaces between or around their components: !prefer_md, not ! prefer_md or !prefer _ md. The YAML parser usually strips whitespace before Quarto sees the tag, but this check exists for the rare cases where some whitespace survives.

Why this happens

If you see this error, the most likely cause is a stray space inserted by an editor or by hand-editing. The recognized tag components themselves never contain spaces.

How to fix

Remove the whitespace from the tag. The tag, including underscores, should be one continuous token immediately after the !.

Related

• Q-1-24 — empty tag component: caused by misplaced underscores, often discovered in the same edit that introduces stray whitespace.
• Q-1-26 — invalid tag character: a broader form of the same check, which catches non-alphanumeric, non-underscore characters in the tag.