Computed Values

Computed values let you name an arithmetic expression once and reuse it later in the same policy.

They are useful when:

• the same calculation appears in multiple conditions
• you want a long expression to have a readable name
• you want to break a policy into smaller numeric steps

Syntax

Define a computed value with :=:

total_requested := **requestedUnits** plus **reservedUnits**.

Reference it later with @name:

A **request** is allowed
if @total_requested is less than **monthlyAllowance**.

:= defines a named calculation in the policy. It is not a mutable variable.

Basic Example

Interactive Example

Reset

Policy Rule

total_requested := **requestedUnits** plus **reservedUnits**.

A **request** is allowed
if @total_requested is less than **monthlyAllowance**.

total_requested := **requestedUnits** plus **reservedUnits**. A **request** is allowed if @total_requested is less than **monthlyAllowance**.

Test Data (JSON)

{
  "requestedUnits": 20,
  "reservedUnits": 9,
  "monthlyAllowance": 100
}

{ "requestedUnits": 20, "reservedUnits": 9, "monthlyAllowance": 100 }

Run

Chaining Computed Values

Computed values can reference earlier computed values:

squared_score := **score** power of 2.
rounded_score := round @squared_score to 2 places.

A **Applicant** is approved
if @rounded_score is greater than 49.

Aggregate Expressions

Computed values work with aggregate expressions too:

order_total := sum of __prices__ of **Order**.
average_price := average of __prices__ of **Order**.

A **Order** qualifies for review
if @order_total is greater than 100
and @average_price is greater than 20.

Input Sources

Computed values can read from:

• selector properties like **score**
• property paths like __prices__ of **Order**
• other computed values like @order_total
• inline arithmetic and math functions

Natural Math Syntax

Computed values support the same arithmetic forms as rule conditions:

rounded := round **score** to 2 places.
total := sum of __scores__ of **Report**.
bounded := clamp(@total, 0, 100).

Numeric Strings

If your input data contains numeric strings, arithmetic still works:

incremented := **score** plus 1.
rounded := round **score** to 1 place.

with input like:

{
  "score": "12.5"
}

This also applies to array aggregates such as sum of and average of.

Relationship to Labels

Computed values defined with := are separate from boolean rule labels like §ageCheck.

• use := when you want a reusable numeric calculation
• use §label when you want one rule to depend on another rule’s pass/fail result
• use @label from the Labels page when reading a value exposed by @@(...)

Example Policy

Interactive Example

Reset

Policy Rule

base_limit := max(100, **manualLimit**, 250).
total := sum of __prices__ of **Order**.
rounded_score := round **score** to 2 places.

A **Order** is approved
if @total is less than or equal to @base_limit
and @rounded_score is greater than 7.5.

base_limit := max(100, **manualLimit**, 250). total := sum of __prices__ of **Order**. rounded_score := round **score** to 2 places. A **Order** is approved if @total is less than or equal to @base_limit and @rounded_score is greater than 7.5.

Test Data (JSON)

{
  "score": "8.125",
  "manualLimit": 180,
  "Order": {
    "prices": ["20", "35", "15"]
  }
}

{ "score": "8.125", "manualLimit": 180, "Order": { "prices": ["20", "35", "15"] } }

Run