---

yaml
---
r: 79369
b: refs/heads/try
c: ab2e83d
h: refs/heads/master
i:
  79367: ebda7dc
v: v3

Author: jbclements

[refs]

@@ -2,7 +2,7 @@
 refs/heads/master: 3e6de6b7da8ee88bf84b0e217900051334be08da
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
 refs/heads/snap-stage3: 60fba4d7d677ec098e6a43014132fe99f7547363
-refs/heads/try: dcc0797a99ef21cddef6bbe847c79ddbcd96c355
+refs/heads/try: ab2e83dd8753833ee572210c20876b0583f6d37e
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b
 refs/heads/try2: 147ecfdd8221e4a4d4e090486829a06da1e0ca3c

branches/try/src/libsyntax/ext/expand.rs

@@ -1410,6 +1410,17 @@ pub fn expand_crate(parse_sess: @mut parse::ParseSess,
     return ret;
 }
 
+// HYGIENIC CONTEXT EXTENSION:
+// all of these functions are for walking over
+// ASTs and making some change to the context of every
+// element that has one. a CtxtFn is a trait-ified
+// version of a closure in (SyntaxContext -> SyntaxContext).
+// the ones defined here include:
+// Renamer - add a rename to a context
+// MultiRenamer - add a set of renames to a context
+// Marker - add a mark to a context
+// Repainter - replace a context (maybe Replacer would be a better name?)
+
 // a function in SyntaxContext -> SyntaxContext
 pub trait CtxtFn{
     fn f(&self, ast::SyntaxContext) -> ast::SyntaxContext;