Tree generating context-free grammars and regular tree grammars are equivalent

We show that it is decidable whether the language generated by a given context-free grammar over a tree alphabet is a tree language. Furthermore, if the answer to this question is “yes”, then we can even effectively construct a regular tree grammar which generates that tree language

Tree generating context-free grammars and regular tree grammars are equivalent

We show that it is decidable whether the language generated by a given context-free grammar over a tree alphabet is a tree language. Furthermore, if the answer to this question is “yes”, then we can even effectively construct a regular tree grammar which generates that tree language