Placeholders

Placeholders let you reference and reuse values from other attributes in your content, helping you maintain consistency and avoid duplication.

For example, in a promotional banner, you can use placeholders to generate the value for the coupon code and the message:

Syntax

The basic syntax for a placeholder is {{attribute}}, where attribute is the path to the attribute you want to insert. You can optionally provide a fallback value by adding a pipe character |, like in {{attribute | fallback value}}.

The attribute paths can use two types of notation:

• Name notation
  For referencing an attribute by its name, like title.
• Index notation
  For referencing a list item by its index, like features[0].

You can combine both notations to reference nested attributes. For example, features[1].label.

Absolute paths

Absolute paths always start from the root of the content, regardless of where the placeholder is located.

Building on the initial example, if the promotion information were nested, you would reference the discount and coupon attributes like this:

Relative paths

Relative paths start with double dots .. and use the location of the placeholder to resolve the path. For example, {{..discount}} references a sibling attribute, and {{..[0]}} references the first item in the parent list.

The equivalent relative paths for the previous example would be:

Fallback values

Lastly, you can optionally provide a fallback value for cases where the reference points to a missing or non-primitive value. When not specified, it defaults to an empty string.

For example, you can use the placeholder {{description | No description}} to fall back to "No description" (or any other text) in the absence of the description attribute, assuming it is optional.

To use a literal character in your default value, you can escape it with a backslash \. For example, you can use {{description | \ No description}} to force a space before the default value.

It is important to note that placeholder behavior depends on the value type of the referenced attribute:

• Text: the reference is inserted into the final value as is.
• Number: the number is formatted and converted to text, following the same behavior as in JavaScript.
• Boolean: the reference is rendered as either true or false.
• Other values: the reference is silently ignored and becomes an empty string in the final value.

Dynamic values

You can also use placeholders to insert user-specific values into your content.

For example, you can use a placeholder to insert the user's name in a greeting message with the help of another attribute:

In this example, the result will be either "Welcome, John!" or "Welcome, guest!" depending on the user's context.

Examples

Here are some examples of placeholders for your quick reference: