Document second argument of multi::length_value
@@ -890,6 +890,7 @@ where
/// `length_value` will return an error.
/// # Arguments
/// * `f` The parser to apply.
+/// * `g` The parser to apply on the subslice.
/// ```rust
/// # #[macro_use] extern crate nom;
/// # use nom::{Err, error::{Error, ErrorKind}, Needed, IResult};
