A nom-based ABNF parser.
Not thoroughly tested, but works with arguably complex ABNFs.
There are some experimental branches. The with_generic_node branch uses an enum...
Rust
enum Node {
Alternation(Vec<Node>>),
Concatenation(Vec<Node>>),
...
}
...which may be more suitable when implementing transformations.
The master branch is a direct transformation of RFC 5234 to code.