{"id":"interpreter-primary-client-of-recursive-subsystem","text":"Interpreter draws on both Composite and Visitor among the GoF patterns: its abstract syntax tree is an instance of Composite (with terminal expressions as leaves and nonterminal expressions as composites), and Visitor is recommended for adding operations such as type-checking, optimization, and code generation to the AST without modifying grammar classes.","truth_value":"IN","source":"","source_url":"","source_hash":"","justifications":[{"type":"SL","antecedents":["interpreter-abstract-syntax-tree-is-composite","visitor-recommended-for-interpreter-extension"],"outlist":[],"label":"Interpreter uniquely requires both Composite's structure and Visitor's extensibility"}],"dependents":["interpreter-recursive-subsystem-safely-complete","interpreter-validates-recursive-subsystem-completeness"],"metadata":{"source_type":"derived","review_result":"pass","repair_action":"softened"},"created_at":"2026-06-17T23:28:16+00:00","updated_at":"2026-06-18T06:15:08+00:00","reviewed_at":"2026-06-18T06:15:08+00:00","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"interpreter-primary-client-of-recursive-subsystem","truth_value":"IN","reason":"SL justification valid","antecedents":["interpreter-abstract-syntax-tree-is-composite","visitor-recommended-for-interpreter-extension"],"label":"Interpreter uniquely requires both Composite's structure and Visitor's extensibility"},{"node":"interpreter-abstract-syntax-tree-is-composite","truth_value":"IN","reason":"premise"},{"node":"visitor-recommended-for-interpreter-extension","truth_value":"IN","reason":"premise"}]}}