---

yaml
---
r: 144838
b: refs/heads/try2
c: 985a92e
h: refs/heads/master
v: v3

Author: jbclements

[refs]

@@ -5,7 +5,7 @@ refs/heads/snap-stage3: 78a7676898d9f80ab540c6df5d4c9ce35bb50463
 refs/heads/try: 519addf6277dbafccbb4159db4b710c37eaa2ec5
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b
-refs/heads/try2: 1a065841172a0824046b1f041bdb1134ba820db8
+refs/heads/try2: 985a92ec123ff05a361bde6af4602282e3851d77
 refs/heads/dist-snap: ba4081a5a8573875fed17545846f6f6902c8ba8d
 refs/tags/release-0.2: c870d2dffb391e14efb05aa27898f1f6333a9596
 refs/tags/release-0.3: b5f0d0f648d9a6153664837026ba1be43d3e2503

branches/try2/src/libsyntax/ast.rs

@@ -81,6 +81,15 @@ impl Ident {
 // storage.
 pub type SyntaxContext = uint;
 
+// the SCTable contains a table of SyntaxContext_'s. It
+// represents a flattened tree structure, to avoid having
+// managed pointers everywhere (that caused an ICE).
+// the mark_memo and rename_memo fields are side-tables
+// that ensure that adding the same mark to the same context
+// gives you back the same context as before. This shouldn't
+// change the semantics--everything here is immutable--but
+// it should cut down on memory use *a lot*; applying a mark
+// to a tree containing 50 identifiers would otherwise generate
 pub struct SCTable {
     table : ~[SyntaxContext_],
     mark_memo : HashMap<(SyntaxContext,Mrk),SyntaxContext>,