The programming language follows a context-free grammar (CFG), which has been written in Backus-Naur Form (BNF). It is technically nonsensical to say "the programming language is BNF". It's like if I were to say "English is a Roman language" because we happen to use the Roman letters for our orthography. Just a technical nitpick.
> BNF is a more expressive language than regexp
The context-free languages are more expressive than the regular languages. BNF is a notation for writing a context-free grammar, and regular expressions are a notation for writing regular languages. (Again, a nitpick of terminology.)
The programming language follows a context-free grammar (CFG), which has been written in Backus-Naur Form (BNF). It is technically nonsensical to say "the programming language is BNF". It's like if I were to say "English is a Roman language" because we happen to use the Roman letters for our orthography. Just a technical nitpick.
> BNF is a more expressive language than regexp
The context-free languages are more expressive than the regular languages. BNF is a notation for writing a context-free grammar, and regular expressions are a notation for writing regular languages. (Again, a nitpick of terminology.)