auto merge of #12807 : pnkfelix/rust/fsk-issue5121-fns-with-early-lifetime-params, r=pnkfelix

Fix issue #5121: Add proper support for early/late distinction for lifetime bindings.

There are some little refactoring cleanups as separate commits; the real meat that has the actual fix is in the final commit.

The original author of the work was @nikomatsakis; I have reviewed it, revised it slightly, refactored it into these separate commits, and done some rebasing work.

Author: bors

src/librustc/front/std_inject.rs

@@ -164,12 +164,12 @@ impl fold::Folder for PreludeInjector {
             segments: vec!(
                 ast::PathSegment {
                     identifier: token::str_to_ident("std"),
-                    lifetimes: opt_vec::Empty,
+                    lifetimes: Vec::new(),
                     types: opt_vec::Empty,
                 },
                 ast::PathSegment {
                     identifier: token::str_to_ident("prelude"),
-                    lifetimes: opt_vec::Empty,
+                    lifetimes: Vec::new(),
                     types: opt_vec::Empty,
                 }),
         };

src/librustc/front/test.rs

@@ -369,7 +369,7 @@ fn path_node(ids: Vec<ast::Ident> ) -> ast::Path {
         global: false,
         segments: ids.move_iter().map(|identifier| ast::PathSegment {
             identifier: identifier,
-            lifetimes: opt_vec::Empty,
+            lifetimes: Vec::new(),
             types: opt_vec::Empty,
         }).collect()
     }
@@ -381,7 +381,7 @@ fn path_node_global(ids: Vec<ast::Ident> ) -> ast::Path {
         global: true,
         segments: ids.move_iter().map(|identifier| ast::PathSegment {
             identifier: identifier,
-            lifetimes: opt_vec::Empty,
+            lifetimes: Vec::new(),
             types: opt_vec::Empty,
         }).collect()
     }

src/librustc/metadata/decoder.rs

@@ -273,7 +273,7 @@ fn item_region_param_defs(item_doc: ebml::Doc, cdata: Cmd)
                                              tag_region_param_def_def_id);
             let def_id = reader::with_doc_data(def_id_doc, parse_def_id);
             let def_id = translate_def_id(cdata, def_id);
-            v.push(ty::RegionParameterDef { ident: ident.name,
+            v.push(ty::RegionParameterDef { name: ident.name,
                                             def_id: def_id });
             true
         });

src/librustc/metadata/encoder.rs

@@ -184,7 +184,7 @@ fn encode_region_param_defs(ebml_w: &mut writer::Encoder,
         ebml_w.start_tag(tag_region_param_def);
 
         ebml_w.start_tag(tag_region_param_def_ident);
-        encode_name(ebml_w, param.ident);
+        encode_name(ebml_w, param.name);
         ebml_w.end_tag();
 
         ebml_w.wr_tagged_str(tag_region_param_def_def_id,

src/librustc/metadata/tyencode.rs

@@ -176,11 +176,11 @@ fn enc_region(w: &mut MemWriter, cx: @ctxt, r: ty::Region) {
             enc_bound_region(w, cx, br);
             mywrite!(w, "]");
         }
-        ty::ReEarlyBound(node_id, index, ident) => {
+        ty::ReEarlyBound(node_id, index, name) => {
             mywrite!(w, "B[{}|{}|{}]",
                      node_id,
                      index,
-                     token::get_name(ident));
+                     token::get_name(name));
         }
         ty::ReFree(ref fr) => {
             mywrite!(w, "f[{}|", fr.scope_id);
@@ -208,10 +208,10 @@ fn enc_bound_region(w: &mut MemWriter, cx: @ctxt, br: ty::BoundRegion) {
         ty::BrAnon(idx) => {
             mywrite!(w, "a{}|", idx);
         }
-        ty::BrNamed(d, s) => {
+        ty::BrNamed(d, name) => {
             mywrite!(w, "[{}|{}]",
                      (cx.ds)(d),
-                     token::get_name(s));
+                     token::get_name(name));
         }
         ty::BrFresh(id) => {
             mywrite!(w, "f{}|", id);

src/librustc/middle/privacy.rs

@@ -13,6 +13,7 @@
 //! which are available for use externally when compiled as a library.
 
 use std::mem::replace;
+use std::vec_ng::Vec;
 
 use metadata::csearch;
 use middle::lint;
@@ -855,7 +856,7 @@ impl<'a> Visitor<()> for PrivacyVisitor<'a> {
                                 debug!("privacy - list {}", pid.node.id);
                                 let seg = ast::PathSegment {
                                     identifier: pid.node.name,
-                                    lifetimes: opt_vec::Empty,
+                                    lifetimes: Vec::new(),
                                     types: opt_vec::Empty,
                                 };
                                 let segs = vec!(seg);