2010-06-01 ago uniform ML environment setup for Isar and PG;
2010-05-31 ago modernized some structure names, keeping a few legacy aliases;
2010-05-15 ago renamed structure OuterSyntax to Outer_Syntax, keeping the old name as alias for some time;
2010-05-15 ago refer directly to structure Keyword and Parse;
2009-10-28 ago Isar.goal: Proof.simple_goal, not raw version;
2009-10-27 ago non-critical atomic accesses;
2009-09-30 ago eliminated dead code;
2009-09-29 ago open_unsynchronized for interactive Isar loop;
2009-09-29 ago explicit indication of Unsynchronized.ref;
2009-09-01 ago removed old Isar document model;
2009-06-06 ago ML_Compiler.exn_message;
2009-06-04 ago uniform (short) ids on both sides;
2009-02-28 ago fixed headers;
2009-02-28 ago moved isabelle_process.ML, isabelle_process.scala, isar.ML, session.ML to Pure/System/ (together with associated Isar commands);