Converting EBNF to BNF

Question

It\'s been a few years since my computer-language class and so I\'ve forgotten the finer points of BNF\'s and EBNF\'s and I don\'t have a textbook next to me. Specifically,

Answer 1

See this page.

Answer 2

Be warned: EBNF as it's listed in the ISO standard also includes exceptions to syntactic rules, which do not have a BNF equivalent. The conversion given by 500 - Internal Server Error only works for the portion of EBNF which overlaps with RBNF/ABNF.