Closure Properties
Context-free languages are closed under the following operations. That is, if L and P are context-free languages, the following languages are context-free as well:
- the union of L and P
- the reversal of L
- the concatenation of L and P
- the Kleene star of L
- the image of L under a homomorphism
- the image of L under an inverse homomorphism
- the cyclic shift of L (the language )
Context-free languages are not closed under complement, intersection, or difference. However, if L is a context-free language and D is a regular language then both their intersection and their difference are context-free languages.
Read more about this topic: Context-free Language
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