Matrices, tables and analysis panels
Typed decision table — first match
A typed decision table evaluated in first-match order: the first row whose conditions all match produces the outcome.
decision.rules@1New DDN source
Why use it?
Expose rule order as a deliberate design decision instead of an accident of presentation.
When it helps
Bounded business rules where precedence must be reviewable line by line.
How to read it
- Read rows top-down: the first fully-matching row wins.
- Type domains on each input gate what a row may claim.
What you need
- The input fields and their domains
- The rule rows in priority order
- The output column
Things to check
- Row order is normative here — reordering rows changes outcomes.
- A gap in the domain is a silent fall-through, not a default row.
Scope of this diagram
Bounded decision-table evaluation against one input record; no arbitrary rule-language execution.
Work with the converted example
- Open the viewer and select
decision_first. Inspect the rendered view and its source. - Open the designer. Keep the selected profile and inspect its legal palette and property controls.
- Change one displayed title or an appropriate data value. Apply the edit and check the resulting diagram.
- Run the verifier and review its diagnostics before moving complete content into review.
- Download your edited DDN source to retain the change.
The example uses the indentation-based ddn-next-1 dialect. The language guide explains reusable definitions, dotted data rows and explicit property blocks.