use rustc_expand::base::{ExtCtxt, Resolver};
use rustc_expand::expand::{AstFragment, ExpansionConfig};
+use rustc_span::hygiene::AstPass;
+use rustc_span::symbol::{kw, sym};
+use rustc_span::{Span, DUMMY_SP};
use smallvec::smallvec;
use syntax::ast::{self, Ident};
use syntax::attr;
use syntax::print::pprust;
use syntax::ptr::P;
use syntax::sess::ParseSess;
-use syntax::symbol::{kw, sym};
use syntax::visit::{self, Visitor};
-use syntax_pos::hygiene::AstPass;
-use syntax_pos::{Span, DUMMY_SP};
struct ProcMacroDerive {
trait_name: ast::Name,