As the number and maturity of platforms supporting the Decision Model and Notation (DMN) standard continues to grow, it is time to take a look at the third Conformance Level defined in DMN. The Friendly Enough Expression Language (FEEL) is the language used by DMN to formalize decision logic in applicable points of a decision model. Conformance Level 3 supplements the notation and modeling in Conformance Level 1 and the decision table support defined in S-FEEL (simple Friendly Enough Expression Language) of Level 2 with the full FEEL expression language. FEEL provides powerful capabilities to satisfy the needs of DMN:
- Built-in types, functions and operators
- Enables a formal expression that can define every decision in a model
- Formal expressions that may be encapsulated as functions • Supports abstraction, composition, and scalability
With this capability in mind, let’s remind ourselves of the stated goals of DMN: