Use `Span` instead of `SyntaxContext` in `Ident`

23 files changed, 146 insertions, 93 deletions

diff --git a/src/libproc_macro/lib.rs b/src/libproc_macro/lib.rs
index ebd5c834fd0..124815a8849 100644
--- a/src/libproc_macro/lib.rs
+++ b/src/libproc_macro/lib.rs
@@ -1097,7 +1097,7 @@ impl TokenTree {
                 }).into();
             },
             self::TokenTree::Term(tt) => {
-                let ident = ast::Ident { name: tt.sym, ctxt: tt.span.0.ctxt() };
+                let ident = ast::Ident::new(tt.sym, tt.span.0);
                 let sym_str = tt.sym.as_str();
                 let token =
                     if sym_str.starts_with("'") { Lifetime(ident) }
diff --git a/src/librustc/hir/lowering.rs b/src/librustc/hir/lowering.rs
index b767ede5faa..c47f67ec740 100644
--- a/src/librustc/hir/lowering.rs
+++ b/src/librustc/hir/lowering.rs
@@ -909,7 +909,7 @@ impl<'a> LoweringContext<'a> {
 
     fn lower_ident(&mut self, ident: Ident) -> Name {
         let ident = ident.modern();
-        if ident.ctxt == SyntaxContext::empty() {
+        if ident.span.ctxt() == SyntaxContext::empty() {
             return ident.name;
         }
         *self.name_map
@@ -2089,10 +2089,7 @@ impl<'a> LoweringContext<'a> {
             name: self.lower_ident(match f.ident {
                 Some(ident) => ident,
                 // FIXME(jseyfried) positional field hygiene
-                None => Ident {
-                    name: Symbol::intern(&index.to_string()),
-                    ctxt: f.span.ctxt(),
-                },
+                None => Ident::new(Symbol::intern(&index.to_string()), f.span),
             }),
             vis: self.lower_visibility(&f.vis, None),
             ty: self.lower_ty(&f.ty, ImplTraitContext::Disallowed),
diff --git a/src/librustc/ich/impls_hir.rs b/src/librustc/ich/impls_hir.rs
index c3b3e10201f..7335511a5a0 100644
--- a/src/librustc/ich/impls_hir.rs
+++ b/src/librustc/ich/impls_hir.rs
@@ -655,7 +655,7 @@ impl<'a> HashStable<StableHashingContext<'a>> for ast::Ident {
                                           hasher: &mut StableHasher<W>) {
         let ast::Ident {
             ref name,
-            ctxt: _ // Ignore this
+            span: _ // Ignore this
         } = *self;
 
         name.hash_stable(hcx, hasher);
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index 72ba199eb24..b920553ec36 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -2088,8 +2088,8 @@ impl<'a, 'gcx, 'tcx> VariantDef {
             return Some(index);
         }
         let mut ident = name.to_ident();
-        while ident.ctxt != SyntaxContext::empty() {
-            ident.ctxt.remove_mark();
+        while ident.span.ctxt() != SyntaxContext::empty() {
+            ident.span.remove_mark();
             if let Some(field) = self.fields.iter().position(|f| f.name.to_ident() == ident) {
                 return Some(field);
             }
@@ -2558,7 +2558,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             LOCAL_CRATE => self.hir.definitions().expansion(scope.index),
             _ => Mark::root(),
         };
-        let scope = match ident.ctxt.adjust(expansion) {
+        let scope = match ident.span.adjust(expansion) {
             Some(macro_def) => self.hir.definitions().macro_def_scope(macro_def),
             None if block == DUMMY_NODE_ID => DefId::local(CRATE_DEF_INDEX), // Dummy DefId
             None => self.hir.get_module_parent(block),
diff --git a/src/librustc_driver/pretty.rs b/src/librustc_driver/pretty.rs
index c5e7fdb30d3..70b73ebb8cd 100644
--- a/src/librustc_driver/pretty.rs
+++ b/src/librustc_driver/pretty.rs
@@ -466,11 +466,11 @@ impl<'a> PrinterSupport for HygieneAnnotation<'a> {
 impl<'a> pprust::PpAnn for HygieneAnnotation<'a> {
     fn post(&self, s: &mut pprust::State, node: pprust::AnnNode) -> io::Result<()> {
         match node {
-            pprust::NodeIdent(&ast::Ident { name, ctxt }) => {
+            pprust::NodeIdent(&ast::Ident { name, span }) => {
                 s.s.space()?;
                 // FIXME #16420: this doesn't display the connections
                 // between syntax contexts
-                s.synth_comment(format!("{}{:?}", name.as_u32(), ctxt))
+                s.synth_comment(format!("{}{:?}", name.as_u32(), span.ctxt()))
             }
             pprust::NodeName(&name) => {
                 s.s.space()?;
diff --git a/src/librustc_privacy/lib.rs b/src/librustc_privacy/lib.rs
index 95be691b30c..d951a7f1cc1 100644
--- a/src/librustc_privacy/lib.rs
+++ b/src/librustc_privacy/lib.rs
@@ -35,7 +35,6 @@ use rustc::util::nodemap::NodeSet;
 use syntax::ast::{self, CRATE_NODE_ID, Ident};
 use syntax::symbol::keywords;
 use syntax_pos::Span;
-use syntax_pos::hygiene::SyntaxContext;
 
 use std::cmp;
 use std::mem::replace;
@@ -495,11 +494,11 @@ struct NamePrivacyVisitor<'a, 'tcx: 'a> {
 impl<'a, 'tcx> NamePrivacyVisitor<'a, 'tcx> {
     // Checks that a field in a struct constructor (expression or pattern) is accessible.
     fn check_field(&mut self,
-                   use_ctxt: SyntaxContext, // Syntax context of the field name at the use site
+                   use_ctxt: Span, // Syntax context of the field name at the use site
                    span: Span, // Span of the field pattern, e.g. `x: 0`
                    def: &'tcx ty::AdtDef, // Definition of the struct or enum
                    field: &'tcx ty::FieldDef) { // Definition of the field
-        let ident = Ident { ctxt: use_ctxt.modern(), ..keywords::Invalid.ident() };
+        let ident = Ident::new(keywords::Invalid.name(), use_ctxt.modern());
         let def_id = self.tcx.adjust_ident(ident, def.did, self.current_item).1;
         if !def.is_enum() && !field.vis.is_accessible_from(def_id, self.tcx) {
             struct_span_err!(self.tcx.sess, span, E0451, "field `{}` of {} `{}` is private",
@@ -573,14 +572,14 @@ impl<'a, 'tcx> Visitor<'tcx> for NamePrivacyVisitor<'a, 'tcx> {
                     for variant_field in &variant.fields {
                         let field = fields.iter().find(|f| f.name.node == variant_field.name);
                         let (use_ctxt, span) = match field {
-                            Some(field) => (field.name.node.to_ident().ctxt, field.span),
-                            None => (base.span.ctxt(), base.span),
+                            Some(field) => (field.name.node.to_ident().span, field.span),
+                            None => (base.span, base.span),
                         };
                         self.check_field(use_ctxt, span, adt, variant_field);
                     }
                 } else {
                     for field in fields {
-                        let use_ctxt = field.name.node.to_ident().ctxt;
+                        let use_ctxt = field.name.node.to_ident().span;
                         let field_def = variant.field_named(field.name.node);
                         self.check_field(use_ctxt, field.span, adt, field_def);
                     }
@@ -599,7 +598,7 @@ impl<'a, 'tcx> Visitor<'tcx> for NamePrivacyVisitor<'a, 'tcx> {
                 let adt = self.tables.pat_ty(pat).ty_adt_def().unwrap();
                 let variant = adt.variant_of_def(def);
                 for field in fields {
-                    let use_ctxt = field.node.name.to_ident().ctxt;
+                    let use_ctxt = field.node.name.to_ident().span;
                     let field_def = variant.field_named(field.node.name);
                     self.check_field(use_ctxt, field.span, adt, field_def);
                 }
diff --git a/src/librustc_resolve/build_reduced_graph.rs b/src/librustc_resolve/build_reduced_graph.rs
index 397590012fd..f7fd190af0c 100644
--- a/src/librustc_resolve/build_reduced_graph.rs
+++ b/src/librustc_resolve/build_reduced_graph.rs
@@ -157,7 +157,7 @@ impl<'a> Resolver<'a> {
 
                     // Disallow `use $crate;`
                     if source.name == keywords::DollarCrate.name() && path.segments.len() == 1 {
-                        let crate_root = self.resolve_crate_root(source.ctxt, true);
+                        let crate_root = self.resolve_crate_root(source.span.ctxt(), true);
                         let crate_name = match crate_root.kind {
                             ModuleKind::Def(_, name) => name,
                             ModuleKind::Block(..) => unreachable!(),
diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index 64d57ea34c2..cb5c6f8ec5f 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -1912,10 +1912,11 @@ impl<'a> Resolver<'a> {
                                       path_span: Span)
                                       -> Option<LexicalScopeBinding<'a>> {
         if ns == TypeNS {
-            ident.ctxt = if ident.name == keywords::SelfType.name() {
-                SyntaxContext::empty() // FIXME(jseyfried) improve `Self` hygiene
+            ident.span = if ident.name == keywords::SelfType.name() {
+                // FIXME(jseyfried) improve `Self` hygiene
+                ident.span.with_ctxt(SyntaxContext::empty())
             } else {
-                ident.ctxt.modern()
+                ident.span.modern()
             }
         }
 
@@ -1931,10 +1932,10 @@ impl<'a> Resolver<'a> {
 
             module = match self.ribs[ns][i].kind {
                 ModuleRibKind(module) => module,
-                MacroDefinition(def) if def == self.macro_def(ident.ctxt) => {
+                MacroDefinition(def) if def == self.macro_def(ident.span.ctxt()) => {
                     // If an invocation of this macro created `ident`, give up on `ident`
                     // and switch to `ident`'s source from the macro definition.
-                    ident.ctxt.remove_mark();
+                    ident.span.remove_mark();
                     continue
                 }
                 _ => continue,
@@ -1954,9 +1955,9 @@ impl<'a> Resolver<'a> {
             }
         }
 
-        ident.ctxt = ident.ctxt.modern();
+        ident.span = ident.span.modern();
         loop {
-            module = unwrap_or!(self.hygienic_lexical_parent(module, &mut ident.ctxt), break);
+            module = unwrap_or!(self.hygienic_lexical_parent(module, &mut ident.span), break);
             let orig_current_module = self.current_module;
             self.current_module = module; // Lexical resolutions can never be a privacy error.
             let result = self.resolve_ident_in_module_unadjusted(
@@ -1980,10 +1981,10 @@ impl<'a> Resolver<'a> {
         }
     }
 
-    fn hygienic_lexical_parent(&mut self, mut module: Module<'a>, ctxt: &mut SyntaxContext)
+    fn hygienic_lexical_parent(&mut self, mut module: Module<'a>, span: &mut Span)
                                -> Option<Module<'a>> {
-        if !module.expansion.is_descendant_of(ctxt.outer()) {
-            return Some(self.macro_def_scope(ctxt.remove_mark()));
+        if !module.expansion.is_descendant_of(span.ctxt().outer()) {
+            return Some(self.macro_def_scope(span.remove_mark()));
         }
 
         if let ModuleKind::Block(..) = module.kind {
@@ -1995,7 +1996,7 @@ impl<'a> Resolver<'a> {
             let parent_expansion = parent.expansion.modern();
             if module_expansion.is_descendant_of(parent_expansion) &&
                parent_expansion != module_expansion {
-                return if parent_expansion.is_descendant_of(ctxt.outer()) {
+                return if parent_expansion.is_descendant_of(span.ctxt().outer()) {
                     Some(parent)
                 } else {
                     None
@@ -2016,9 +2017,9 @@ impl<'a> Resolver<'a> {
                                record_used: bool,
                                span: Span)
                                -> Result<&'a NameBinding<'a>, Determinacy> {
-        ident.ctxt = ident.ctxt.modern();
+        ident.span = ident.span.modern();
         let orig_current_module = self.current_module;
-        if let Some(def) = ident.ctxt.adjust(module.expansion) {
+        if let Some(def) = ident.span.adjust(module.expansion) {
             self.current_module = self.macro_def_scope(def);
         }
         let result = self.resolve_ident_in_module_unadjusted(
@@ -2108,8 +2109,8 @@ impl<'a> Resolver<'a> {
                 // If an invocation of this macro created `ident`, give up on `ident`
                 // and switch to `ident`'s source from the macro definition.
                 MacroDefinition(def) => {
-                    if def == self.macro_def(ident.ctxt) {
-                        ident.ctxt.remove_mark();
+                    if def == self.macro_def(ident.span.ctxt()) {
+                        ident.span.remove_mark();
                     }
                 }
                 _ => {
@@ -2873,7 +2874,7 @@ impl<'a> Resolver<'a> {
             }
             if path.len() == 1 && this.self_type_is_available(span) {
                 if let Some(candidate) = this.lookup_assoc_candidate(ident.node, ns, is_expected) {
-                    let self_is_available = this.self_value_is_available(path[0].node.ctxt, span);
+                    let self_is_available = this.self_value_is_available(path[0].node.span, span);
                     match candidate {
                         AssocSuggestion::Field => {
                             err.span_suggestion(span, "try",
@@ -3084,9 +3085,9 @@ impl<'a> Resolver<'a> {
         if let Some(LexicalScopeBinding::Def(def)) = binding { def != Def::Err } else { false }
     }
 
-    fn self_value_is_available(&mut self, ctxt: SyntaxContext, span: Span) -> bool {
-        let ident = Ident { name: keywords::SelfValue.name(), ctxt: ctxt };
-        let binding = self.resolve_ident_in_lexical_scope(ident, ValueNS, false, span);
+    fn self_value_is_available(&mut self, self_span: Span, path_span: Span) -> bool {
+        let ident = Ident::new(keywords::SelfValue.name(), self_span);
+        let binding = self.resolve_ident_in_lexical_scope(ident, ValueNS, false, path_span);
         if let Some(LexicalScopeBinding::Def(def)) = binding { def != Def::Err } else { false }
     }
 
@@ -3219,11 +3220,11 @@ impl<'a> Resolver<'a> {
             let name = ident.node.name;
 
             if i == 0 && ns == TypeNS && name == keywords::SelfValue.name() {
-                let mut ctxt = ident.node.ctxt.modern();
+                let mut ctxt = ident.node.span.ctxt().modern();
                 module = Some(self.resolve_self(&mut ctxt, self.current_module));
                 continue
             } else if allow_super && ns == TypeNS && name == keywords::Super.name() {
-                let mut ctxt = ident.node.ctxt.modern();
+                let mut ctxt = ident.node.span.ctxt().modern();
                 let self_module = match i {
                     0 => self.resolve_self(&mut ctxt, self.current_module),
                     _ => module.unwrap(),
@@ -3245,11 +3246,11 @@ impl<'a> Resolver<'a> {
                    (i == 1 && name == keywords::Crate.name() &&
                               path[0].node.name == keywords::CrateRoot.name()) {
                     // `::a::b` or `::crate::a::b`
-                    module = Some(self.resolve_crate_root(ident.node.ctxt, false));
+                    module = Some(self.resolve_crate_root(ident.node.span.ctxt(), false));
                     continue
                 } else if i == 0 && name == keywords::DollarCrate.name() {
                     // `$crate::a::b`
-                    module = Some(self.resolve_crate_root(ident.node.ctxt, true));
+                    module = Some(self.resolve_crate_root(ident.node.span.ctxt(), true));
                     continue
                 } else if i == 1 && !token::is_path_segment_keyword(ident.node) {
                     let prev_name = path[0].node.name;
@@ -3771,12 +3772,12 @@ impl<'a> Resolver<'a> {
             }
         }
 
-        ident.ctxt = ident.ctxt.modern();
+        ident.span = ident.span.modern();
         let mut search_module = self.current_module;
         loop {
             self.get_traits_in_module_containing_item(ident, ns, search_module, &mut found_traits);
             search_module =
-                unwrap_or!(self.hygienic_lexical_parent(search_module, &mut ident.ctxt), break);
+                unwrap_or!(self.hygienic_lexical_parent(search_module, &mut ident.span), break);
         }
 
         if let Some(prelude) = self.prelude {
@@ -3808,7 +3809,7 @@ impl<'a> Resolver<'a> {
         for &(trait_name, binding) in traits.as_ref().unwrap().iter() {
             let module = binding.module().unwrap();
             let mut ident = ident;
-            if ident.ctxt.glob_adjust(module.expansion, binding.span.ctxt().modern()).is_none() {
+            if ident.span.glob_adjust(module.expansion, binding.span.ctxt().modern()).is_none() {
                 continue
             }
             if self.resolve_ident_in_module_unadjusted(module, ident, ns, false, false, module.span)
diff --git a/src/librustc_resolve/macros.rs b/src/librustc_resolve/macros.rs
index 0692a1e0d7f..289556cd45e 100644
--- a/src/librustc_resolve/macros.rs
+++ b/src/librustc_resolve/macros.rs
@@ -140,7 +140,7 @@ impl<'a> base::Resolver for Resolver<'a> {
                 let ident = path.segments[0].identifier;
                 if ident.name == keywords::DollarCrate.name() {
                     path.segments[0].identifier.name = keywords::CrateRoot.name();
-                    let module = self.0.resolve_crate_root(ident.ctxt, true);
+                    let module = self.0.resolve_crate_root(ident.span.ctxt(), true);
                     if !module.is_local() {
                         let span = path.segments[0].span;
                         path.segments.insert(1, match module.kind {
@@ -534,7 +534,7 @@ impl<'a> Resolver<'a> {
             }
 
             module = match module {
-                Some(module) => self.hygienic_lexical_parent(module, &mut ident.ctxt),
+                Some(module) => self.hygienic_lexical_parent(module, &mut ident.span),
                 None => return potential_illegal_shadower,
             }
         }
diff --git a/src/librustc_resolve/resolve_imports.rs b/src/librustc_resolve/resolve_imports.rs
index 7036bdd0e2b..90a90d73153 100644
--- a/src/librustc_resolve/resolve_imports.rs
+++ b/src/librustc_resolve/resolve_imports.rs
@@ -238,7 +238,7 @@ impl<'a> Resolver<'a> {
             }
             let module = unwrap_or!(directive.imported_module.get(), return Err(Undetermined));
             let (orig_current_module, mut ident) = (self.current_module, ident.modern());
-            match ident.ctxt.glob_adjust(module.expansion, directive.span.ctxt().modern()) {
+            match ident.span.glob_adjust(module.expansion, directive.span.ctxt().modern()) {
                 Some(Some(def)) => self.current_module = self.macro_def_scope(def),
                 Some(None) => {}
                 None => continue,
@@ -398,7 +398,7 @@ impl<'a> Resolver<'a> {
         // Define `binding` in `module`s glob importers.
         for directive in module.glob_importers.borrow_mut().iter() {
             let mut ident = ident.modern();
-            let scope = match ident.ctxt.reverse_glob_adjust(module.expansion,
+            let scope = match ident.span.reverse_glob_adjust(module.expansion,
                                                              directive.span.ctxt().modern()) {
                 Some(Some(def)) => self.macro_def_scope(def),
                 Some(None) => directive.parent,
@@ -623,7 +623,7 @@ impl<'a, 'b:'a> ImportResolver<'a, 'b> {
                                          "crate root imports need to be explicitly named: \
                                           `use crate as name;`".to_string()));
                         } else {
-                            Some(self.resolve_crate_root(source.ctxt.modern(), false))
+                            Some(self.resolve_crate_root(source.span.ctxt().modern(), false))
                         }
                     } else if is_extern && !token::is_path_segment_keyword(source) {
                         let crate_id =
@@ -860,7 +860,7 @@ impl<'a, 'b:'a> ImportResolver<'a, 'b> {
             resolution.borrow().binding().map(|binding| (ident, binding))
         }).collect::<Vec<_>>();
         for ((mut ident, ns), binding) in bindings {
-            let scope = match ident.ctxt.reverse_glob_adjust(module.expansion,
+            let scope = match ident.span.reverse_glob_adjust(module.expansion,
                                                              directive.span.ctxt().modern()) {
                 Some(Some(def)) => self.macro_def_scope(def),
                 Some(None) => self.current_module,
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index 27e0f6ad6dd..6d85e949d6b 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -3213,10 +3213,8 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                     if !tuple_like { continue }
 
                     debug!("tuple struct named {:?}",  base_t);
-                    let ident = ast::Ident {
-                        name: Symbol::intern(&idx.node.to_string()),
-                        ctxt: idx.span.ctxt().modern(),
-                    };
+                    let ident =
+                        ast::Ident::new(Symbol::intern(&idx.node.to_string()), idx.span.modern());
                     let (ident, def_scope) =
                         self.tcx.adjust_ident(ident, base_def.did, self.body_id);
                     let fields = &base_def.non_enum_variant().fields;
diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index 9d0c85a34f9..ec5dd7dfd17 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -150,7 +150,7 @@ impl PathSegment {
     }
     pub fn crate_root(span: Span) -> Self {
         PathSegment {
-            identifier: Ident { ctxt: span.ctxt(), ..keywords::CrateRoot.ident() },
+            identifier: Ident::new(keywords::CrateRoot.name(), span),
             span,
             parameters: None,
         }
diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index 5a735be55c0..1e264369f91 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -876,8 +876,8 @@ impl<'a> ExtCtxt<'a> {
         ast::Ident::from_str(st)
     }
     pub fn std_path(&self, components: &[&str]) -> Vec<ast::Ident> {
-        let def_site = SyntaxContext::empty().apply_mark(self.current_expansion.mark);
-        iter::once(Ident { ctxt: def_site, ..keywords::DollarCrate.ident() })
+        let def_site = DUMMY_SP.apply_mark(self.current_expansion.mark);
+        iter::once(Ident::new(keywords::DollarCrate.name(), def_site))
             .chain(components.iter().map(|s| self.ident_of(s)))
             .collect()
     }
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index 105de13b976..31072159ab3 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -1378,7 +1378,7 @@ pub struct Marker(pub Mark);
 
 impl Folder for Marker {
     fn fold_ident(&mut self, mut ident: Ident) -> Ident {
-        ident.ctxt = ident.ctxt.apply_mark(self.0);
+        ident.span = ident.span.apply_mark(self.0);
         ident
     }
 
diff --git a/src/libsyntax/ext/tt/quoted.rs b/src/libsyntax/ext/tt/quoted.rs
index f324edeb117..01b971976a7 100644
--- a/src/libsyntax/ext/tt/quoted.rs
+++ b/src/libsyntax/ext/tt/quoted.rs
@@ -289,14 +289,11 @@ where
             // `tree` is followed by an `ident`. This could be `$meta_var` or the `$crate` special
             // metavariable that names the crate of the invokation.
             Some(tokenstream::TokenTree::Token(ident_span, ref token)) if token.is_ident() => {
-                let (ident, _) = token.ident().unwrap();
+                let (ident, is_raw) = token.ident().unwrap();
                 let span = ident_span.with_lo(span.lo());
-                if ident.name == keywords::Crate.name() {
-                    let ident = ast::Ident {
-                        name: keywords::DollarCrate.name(),
-                        ..ident
-                    };
-                    TokenTree::Token(span, token::Ident(ident, false))
+                if ident.name == keywords::Crate.name() && !is_raw {
+                    let ident = ast::Ident::new(keywords::DollarCrate.name(), ident.span);
+                    TokenTree::Token(span, token::Ident(ident, is_raw))
                 } else {
                     TokenTree::MetaVar(span, ident)
                 }
diff --git a/src/libsyntax/ext/tt/transcribe.rs b/src/libsyntax/ext/tt/transcribe.rs
index 3f01d5ec6dd..12ada3bdbc0 100644
--- a/src/libsyntax/ext/tt/transcribe.rs
+++ b/src/libsyntax/ext/tt/transcribe.rs
@@ -166,7 +166,7 @@ pub fn transcribe(cx: &ExtCtxt,
                     }
                 } else {
                     let ident =
-                        Ident { ctxt: ident.ctxt.apply_mark(cx.current_expansion.mark), ..ident };
+                        Ident::new(ident.name, ident.span.apply_mark(cx.current_expansion.mark));
                     sp = sp.with_ctxt(sp.ctxt().apply_mark(cx.current_expansion.mark));
                     result.push(TokenTree::Token(sp, token::Dollar).into());
                     result.push(TokenTree::Token(sp, token::Token::from_ast_ident(ident)).into());
diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index 068929c8948..152c4c31eb3 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -76,7 +76,7 @@ impl<'a> StringReader<'a> {
     fn mk_ident(&self, string: &str) -> Ident {
         let mut ident = Ident::from_str(string);
         if let Some(span) = self.override_span {
-            ident.ctxt = span.ctxt();
+            ident.span = span;
         }
         ident
     }
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index 1bed6109dd2..30be2389e7e 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -743,7 +743,7 @@ pub trait PrintState<'a> {
                        segment.identifier.name != keywords::DollarCrate.name() {
                         self.writer().word(&segment.identifier.name.as_str())?;
                     } else if segment.identifier.name == keywords::DollarCrate.name() {
-                        self.print_dollar_crate(segment.identifier.ctxt)?;
+                        self.print_dollar_crate(segment.identifier.span.ctxt())?;
                     }
                 }
                 self.writer().space()?;
@@ -2424,7 +2424,7 @@ impl<'a> State<'a> {
                 self.print_path_parameters(parameters, colons_before_params)?;
             }
         } else if segment.identifier.name == keywords::DollarCrate.name() {
-            self.print_dollar_crate(segment.identifier.ctxt)?;
+            self.print_dollar_crate(segment.identifier.span.ctxt())?;
         }
         Ok(())
     }
diff --git a/src/libsyntax_ext/concat_idents.rs b/src/libsyntax_ext/concat_idents.rs
index d513008f0e2..2b80d698764 100644
--- a/src/libsyntax_ext/concat_idents.rs
+++ b/src/libsyntax_ext/concat_idents.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 use syntax::ast;
+use syntax::codemap::DUMMY_SP;
 use syntax::ext::base::*;
 use syntax::ext::base;
 use syntax::feature_gate;
@@ -16,7 +17,6 @@ use syntax::parse::token;
 use syntax::ptr::P;
 use syntax_pos::Span;
 use syntax_pos::symbol::Symbol;
-use syntax_pos::hygiene::SyntaxContext;
 use syntax::tokenstream::TokenTree;
 
 pub fn expand_syntax_ext<'cx>(cx: &'cx mut ExtCtxt,
@@ -53,11 +53,8 @@ pub fn expand_syntax_ext<'cx>(cx: &'cx mut ExtCtxt,
             }
         }
     }
-    let res = ast::Ident {
-        name: Symbol::intern(&res_str),
-        ctxt: SyntaxContext::empty().apply_mark(cx.current_expansion.mark),
-    };
-
+    let res = ast::Ident::new(Symbol::intern(&res_str),
+                              DUMMY_SP.apply_mark(cx.current_expansion.mark));
     struct Result {
         ident: ast::Ident,
         span: Span,
diff --git a/src/libsyntax_ext/deriving/generic/ty.rs b/src/libsyntax_ext/deriving/generic/ty.rs
index cc3e8b6e6b7..25a29694488 100644
--- a/src/libsyntax_ext/deriving/generic/ty.rs
+++ b/src/libsyntax_ext/deriving/generic/ty.rs
@@ -18,10 +18,9 @@ use syntax::ast;
 use syntax::ast::{Expr, GenericParam, Generics, Ident, SelfKind};
 use syntax::ext::base::ExtCtxt;
 use syntax::ext::build::AstBuilder;
-use syntax::codemap::respan;
+use syntax::codemap::{respan, DUMMY_SP};
 use syntax::ptr::P;
 use syntax_pos::Span;
-use syntax_pos::hygiene::SyntaxContext;
 use syntax_pos::symbol::keywords;
 
 /// The types of pointers
@@ -93,8 +92,8 @@ impl<'a> Path<'a> {
             PathKind::Global => cx.path_all(span, true, idents, lt, tys, Vec::new()),
             PathKind::Local => cx.path_all(span, false, idents, lt, tys, Vec::new()),
             PathKind::Std => {
-                let def_site = SyntaxContext::empty().apply_mark(cx.current_expansion.mark);
-                idents.insert(0, Ident { ctxt: def_site, ..keywords::DollarCrate.ident() });
+                let def_site = DUMMY_SP.apply_mark(cx.current_expansion.mark);
+                idents.insert(0, Ident::new(keywords::DollarCrate.name(), def_site));
                 cx.path_all(span, false, idents, lt, tys, Vec::new())
             }
         }
diff --git a/src/libsyntax_pos/hygiene.rs b/src/libsyntax_pos/hygiene.rs
index aba71bd0468..c180563450f 100644
--- a/src/libsyntax_pos/hygiene.rs
+++ b/src/libsyntax_pos/hygiene.rs
@@ -123,7 +123,7 @@ pub struct HygieneData {
     marks: Vec<MarkData>,
     syntax_contexts: Vec<SyntaxContextData>,
     markings: HashMap<(SyntaxContext, Mark), SyntaxContext>,
-    gensym_to_ctxt: HashMap<Symbol, SyntaxContext>,
+    gensym_to_ctxt: HashMap<Symbol, Span>,
 }
 
 impl HygieneData {
@@ -461,7 +461,7 @@ impl Symbol {
     pub fn from_ident(ident: Ident) -> Symbol {
         HygieneData::with(|data| {
             let gensym = ident.name.gensymed();
-            data.gensym_to_ctxt.insert(gensym, ident.ctxt);
+            data.gensym_to_ctxt.insert(gensym, ident.span);
             gensym
         })
     }
@@ -469,7 +469,7 @@ impl Symbol {
     pub fn to_ident(self) -> Ident {
         HygieneData::with(|data| {
             match data.gensym_to_ctxt.get(&self) {
-                Some(&ctxt) => Ident { name: self.interned(), ctxt: ctxt },
+                Some(&span) => Ident::new(self.interned(), span),
                 None => Ident::with_empty_ctxt(self),
             }
         })
diff --git a/src/libsyntax_pos/lib.rs b/src/libsyntax_pos/lib.rs
index eb345200f41..8b2ebfef250 100644
--- a/src/libsyntax_pos/lib.rs
+++ b/src/libsyntax_pos/lib.rs
@@ -50,7 +50,7 @@ extern crate serialize as rustc_serialize; // used by deriving
 extern crate unicode_width;
 
 pub mod hygiene;
-pub use hygiene::{SyntaxContext, ExpnInfo, ExpnFormat, NameAndSpan, CompilerDesugaringKind};
+pub use hygiene::{Mark, SyntaxContext, ExpnInfo, ExpnFormat, NameAndSpan, CompilerDesugaringKind};
 
 mod span_encoding;
 pub use span_encoding::{Span, DUMMY_SP};
@@ -422,6 +422,52 @@ impl Span {
             if end.ctxt == SyntaxContext::empty() { end.ctxt } else { span.ctxt },
         )
     }
+
+    #[inline]
+    pub fn apply_mark(self, mark: Mark) -> Span {
+        let span = self.data();
+        span.with_ctxt(span.ctxt.apply_mark(mark))
+    }
+
+    #[inline]
+    pub fn remove_mark(&mut self) -> Mark {
+        let mut span = self.data();
+        let mark = span.ctxt.remove_mark();
+        *self = Span::new(span.lo, span.hi, span.ctxt);
+        mark
+    }
+
+    #[inline]
+    pub fn adjust(&mut self, expansion: Mark) -> Option<Mark> {
+        let mut span = self.data();
+        let mark = span.ctxt.adjust(expansion);
+        *self = Span::new(span.lo, span.hi, span.ctxt);
+        mark
+    }
+
+    #[inline]
+    pub fn glob_adjust(&mut self, expansion: Mark, glob_ctxt: SyntaxContext)
+                       -> Option<Option<Mark>> {
+        let mut span = self.data();
+        let mark = span.ctxt.glob_adjust(expansion, glob_ctxt);
+        *self = Span::new(span.lo, span.hi, span.ctxt);
+        mark
+    }
+
+    #[inline]
+    pub fn reverse_glob_adjust(&mut self, expansion: Mark, glob_ctxt: SyntaxContext)
+                               -> Option<Option<Mark>> {
+        let mut span = self.data();
+        let mark = span.ctxt.reverse_glob_adjust(expansion, glob_ctxt);
+        *self = Span::new(span.lo, span.hi, span.ctxt);
+        mark
+    }
+
+    #[inline]
+    pub fn modern(self) -> Span {
+        let span = self.data();
+        span.with_ctxt(span.ctxt.modern())
+    }
 }
 
 #[derive(Clone, Debug)]
diff --git a/src/libsyntax_pos/symbol.rs b/src/libsyntax_pos/symbol.rs
index 098eafef258..661a28d8375 100644
--- a/src/libsyntax_pos/symbol.rs
+++ b/src/libsyntax_pos/symbol.rs
@@ -13,21 +13,27 @@
 //! type, and vice versa.
 
 use hygiene::SyntaxContext;
-use GLOBALS;
+use {Span, DUMMY_SP, GLOBALS};
 
 use serialize::{Decodable, Decoder, Encodable, Encoder};
 use std::collections::HashMap;
 use std::fmt;
+use std::hash::{Hash, Hasher};
 
-#[derive(Copy, Clone, PartialEq, Eq, Hash)]
+#[derive(Copy, Clone, Eq)]
 pub struct Ident {
     pub name: Symbol,
-    pub ctxt: SyntaxContext,
+    pub span: Span,
 }
 
 impl Ident {
+    #[inline]
+    pub const fn new(name: Symbol, span: Span) -> Ident {
+        Ident { name, span }
+    }
+    #[inline]
     pub const fn with_empty_ctxt(name: Symbol) -> Ident {
-        Ident { name: name, ctxt: SyntaxContext::empty() }
+        Ident::new(name, DUMMY_SP)
     }
 
     /// Maps a string to an identifier with an empty syntax context.
@@ -36,17 +42,30 @@ impl Ident {
     }
 
     pub fn without_first_quote(&self) -> Ident {
-        Ident { name: Symbol::from(self.name.as_str().trim_left_matches('\'')), ctxt: self.ctxt }
+        Ident::new(Symbol::from(self.name.as_str().trim_left_matches('\'')), self.span)
     }
 
     pub fn modern(self) -> Ident {
-        Ident { name: self.name, ctxt: self.ctxt.modern() }
+        Ident::new(self.name, self.span.modern())
+    }
+}
+
+impl PartialEq for Ident {
+    fn eq(&self, rhs: &Self) -> bool {
+        self.name == rhs.name && self.span.ctxt() == rhs.span.ctxt()
+    }
+}
+
+impl Hash for Ident {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.name.hash(state);
+        self.span.ctxt().hash(state);
     }
 }
 
 impl fmt::Debug for Ident {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "{}{:?}", self.name, self.ctxt)
+        write!(f, "{}{:?}", self.name, self.span.ctxt())
     }
 }
 
@@ -58,7 +77,7 @@ impl fmt::Display for Ident {
 
 impl Encodable for Ident {
     fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
-        if self.ctxt.modern() == SyntaxContext::empty() {
+        if self.span.ctxt().modern() == SyntaxContext::empty() {
             s.emit_str(&self.name.as_str())
         } else { // FIXME(jseyfried) intercrate hygiene
             let mut string = "#".to_owned();