The known and certain operators are used on rule conditions and cause the condition to evaluate a predictable way when the underlying attribute in the condition has a particular value.
| Operator | Example |
|---|---|
| certain |
the applicant is eligible for the benefit if it is certain whether or not the applicant is entitled to a payment or the applicant's eligibility status is certain |
| uncertain |
the outcome is unclear if it is uncertain whether or not the means have been achieved or the status of the investigation is uncertain |
| known |
the interview has been completed if it is known whether or not the applicant is eligible for a payment or the applicant's rate of benefit is known |
| unknown |
the generic heading should be shown if it is unknown whether or not the applicant is eligible or the applicant's rate of entitlement in unknown |
| currently known |
the income details are available if the applicant's income is currently known |
The known operator is used to ascertain whether an issue has been addressed by the user. The known operator creates a condition that evaluates to true when the attribute used by the condition has a value, no matter what that value is. It is commonly used in procedural rules that drive an investigation. For example, forcing attributes to be known in a particular order before determining a goal (eg forcing a particular screen flow rather than letting the rulebase dictate the screen display order).
The currently known operator is used to test whether an attribute is known, without causing it to be brought up in the question search and asked of the user, ie it will test the current state of the attribute. In the example above, if the applicant's income is unknown, the conclusion will be inferred to false.
The unknown operator is most commonly used for defaulting values in the rulebase where the user has the option of providing an overriding value (either directly or through an inferred attribute). For example:
the team's game point total = the team's points from round 1 + the team's points from round 2 + the team's points from round 3
| the team's points from round 1 | |
|---|---|
| 0 | the team's points from round 1 (as recorded by the team) is unknown |
| the team's points from round 1 (as recorded by the team) | otherwise |
| the team's points from round 2 | |
|---|---|
| 0 | the team's points from round 2 (as recorded by the team) is unknown |
| the team's points from round 2 (as recorded by the team) |
otherwise |
| the team's points from round 3 | |
|---|---|
| 0 | the team's points from round 3 (as recorded by the team) is unknown |
| the team's points from round 3 (as recorded by the team) | otherwise |
These operators can be used to control the visibility of attributes and text on screens and in generated documentation.
TIP: The localized syntax for these functions may be viewed:
See also: