patternthat

Patternthat is a concept in software engineering and data processing that describes the separation of pattern specification from pattern application. In this approach, a pattern is declared in a pattern description language and stored in a registry or repository, while a pattern engine or binder resolves the specification to concrete runtime components to realize the pattern in a given context. This separation aims to improve flexibility and reuse by allowing the same pattern description to be realized with different implementations.

Origin and usage of the term patternthat are largely scholarly and experimental. It is not a widely standardized methodology, and references to it often appear in case studies, prototypes, or discussions about declarative pattern specification rather than formal design guidelines. The concept is used to illustrate how modular pattern definitions can be swapped or extended without altering the core application logic.

Architecture and implementation typically involve three layers: a pattern specification layer, a binding or resolution layer, and an execution layer. The specification layer declares constraints, structure, and behavior with placeholders. The binding layer maps placeholders to concrete components at runtime, enabling dynamic adaptation. The execution layer enacts the realized pattern within the running system.

Applications span user interface theming, data transformation pipelines, and rule-based engines, as well as domain-specific languages for modular software design. Advantages include modularity, reuse, and runtime flexibility, while challenges cover potential performance overhead and increased debugging complexity.

See also: design patterns, pattern matching, declarative programming, dependency injection, domain-specific languages.