pub fn read_number<T>(text: &[u8]) -> Result<T, Error>where T: Ten + From<u8> + Add<T, Output = T> + Mul<T, Output = T> + Sub<T, Output = T>,
Retrieve an integer in text form.
All bytes in the text must be within the range b’0’ and b’9’ The text must also not be empty nor have more than 9 characters.