Labels

Labels let you name rules and reference them from other rules, enabling composable policies.

Very Important Labels cannot have spaces in them.

Defining Labels

Add a label before the article. The label ends with a period:

AgeCheck. A **Person** passes the age check
  if __age__ of **Person** is greater than or equal to 18.

Labels can use dot notation for hierarchical naming:

theory.check. A **Person** passes the theory test
  if __theory_score__ of **Person** is greater than or equal to 43.

practical.check. A **Person** passes the practical test
  if __practical_score__ of **Person** is greater than or equal to 40.

Referencing Labels with §

Use § (or $) to reference a labeled rule from another rule:

A **Person** passes the full test
  if §theory.check passes
  and §practical.check passes.

The § reference evaluates the referenced rule and uses its result as a condition.

Label Predicates

When referencing a label, you can use a predicate to describe the expected outcome:

Predicate	Example
passes	§ageCheck passes
succeeds	§theory.check succeeds
clears	§backgroundCheck clears
qualifies	§eligibility qualifies
meets requirements	§minimumAge meets requirements
satisfies	§criteria satisfies
is valid	§emailCheck is valid
is approved	§review is approved
has passed	§exam has passed
is authorized	§access is authorized
is certified	§training is certified
is permitted	§action is permitted
is satisfied	§condition is satisfied

Full Example

Interactive Example

Reset

Policy Rule

AgeCheck. A **user** passes the age check if __age__ of **user** is greater than or equal to 18. StatusCheck. A **user** passes the status check if __status__ of **user** is equal to "active". A **user** is eligible if §AgeCheck passes and §StatusCheck passes.

Test Data (JSON)

{ "user": { "age": 25, "status": "active" } }

▶ Run

Try changing status to "suspended" — the age check will pass but the status check will fail, causing the overall rule to fail.

Rule References (without labels)

You can also reference rules by their outcome, without using labels:

A **user** passes the age check
  if __age__ of **user** is greater than or equal to 18.

A **user** is eligible
  if the **user** passes the age check.

This form matches the rule by its selector and outcome text.