Variables

Variables

A variable is a short value used in many places: a product name, a base URL, a current version.

Defining them

variables.yaml, beside your pages:

product_name: Staleless
api_url: https://api.staleless.com
current_version: "2.5"

Using them

Double braces, anywhere in a page or a snippet:

Call `{{api_url}}/v1/pages` to list every published page.

A variable that is not defined fails the undefined-variable rule. A page cannot be committed with a brace expression that would reach a reader unresolved.

Where they are resolved

Variables are resolved at build time, so:

• the published page contains the value, not the expression;
• search indexes the value, so a reader searching for your API host finds the page;
• the content API returns the value, because the caller is rendering the page in their own product and has no variable table;
• Ask answers from the value.

Quoting numbers

YAML reads 2.5 as a number and 2.50 as 2.5. Quote a version:

current_version: "2.50"

What a variable is not

A variable is a scalar. It cannot hold a block, a list or conditional content. For a block, use a snippet.

Note

Changing a variable changes every page that uses it. The writer previews which pages are affected before you commit.