{"id":"singleton-constructor-protected-not-private","text":"The Singleton constructor is declared protected (not private) to allow subclassing while still preventing direct external instantiation.","truth_value":"IN","source":"entries/2026/06/17/gof-oo-chunk-10.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{"last_premise_reviewed":"2026-06-17T18:19:22","premise_review_result":"pass"},"created_at":"2026-06-17T21:30:27+00:00","updated_at":"2026-06-17T21:30:27+00:00","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"singleton-constructor-protected-not-private","truth_value":"IN","reason":"premise"}]}}