Tag
context-free-grammars
- Aug 16, 2026 Closure Gaps in Context-Free Languages Context-free languages are closed under union and star but not under intersection or complement, and the two failures are the same failure seen from two sides. computation theory
- Apr 24, 2022 Derivations, Sentential Forms, and What a Parse Tree Actually Records How a grammar rewrites strings step by step, why leftmost derivations and parse trees are two views of one object, and where the correspondence breaks when a grammar is ambiguous. computation theory