Combine the error types.

src/parser/document.rs

@@ -1,3 +1,6 @@
+use crate::error::CustomError;
+use crate::error::MyError;
+use crate::error::Res;
 use crate::parser::comment::comment;
 use crate::parser::element_parser::element;
 use crate::parser::exiting::ExitClass;
@@ -25,7 +28,6 @@ use nom::multi::many_till;
 use nom::sequence::tuple;
 
 use super::element::Element;
-use super::error::Res;
 use super::object::Object;
 use super::parser_with_context::parser_with_context;
 use super::source::Source;