2011-09-19 ago refined Symbol.is_symbolic -- cover recoded versions as well;
2011-09-17 ago Symbol.explode as in ML;
2011-08-17 ago some convenience actions/shortcuts for control symbols;
2011-08-13 ago tuned;
2011-07-09 ago tuned signature;
2011-07-07 ago explicit indication of type Symbol.Symbol;
2011-07-07 ago simplified Symbol based on lazy Symbol.Interpretation -- reduced odd "functorial style";
2011-07-05 ago simplified Symbol.iterator: produce strings, which are mostly preallocated;
2011-06-22 ago clarified decoded control symbols;
2011-06-21 ago more uniform treatment of recode_set/recode_map;
2011-06-21 ago tuned iteration over short symbols;
2011-06-21 ago Symbol.is_ctrl: handle decoded version as well;
2011-06-21 ago some support for user symbol fonts;
2011-06-19 ago names for control symbols without "^", which is relevant for completion;
2011-06-19 ago some unicode chars for special control symbols;
2011-06-18 ago do not control malformed symbols;
2011-06-18 ago basic support for extended syntax styles: sub/superscript;
2011-06-17 ago recovered markup for non-alphabetic keywords;
2010-11-13 ago proper escape in regex;
2010-11-13 ago treat Unicode "replacement character" (i.e. decoding error) is malformed;
2010-11-13 ago simplified/robustified treatment of malformed symbols, which are now fully internalized (total Symbol.explode etc.);
2010-11-13 ago tuned;
2010-11-08 ago explicitly check uniqueness of symbol recoding;
2010-08-30 ago Command.newlines: account for physical newlines;
2010-08-18 ago more efficient Markup_Tree, based on branches sorted by quasi-order;
2010-06-26 ago treat alternative newline symbols as in Isabelle/ML;
2010-05-11 ago predefined spaces;
2010-05-09 ago static Symbol.spaces;
2010-03-29 ago adapted to Scala 2.8.0 Beta1 -- with notable changes to scala.collection;
2010-01-11 ago clarified Symbol.is_plain/is_wellformed -- is_closed was rejecting plain backslashes;
2009-12-28 ago some sanity checks for symbol interpretation;
2009-12-20 ago refined some Symbol operations/signatures;
2009-12-19 ago refined some Symbol operations/signatures;
2009-12-19 ago added symbol classification;
2009-12-17 ago tuned signature;
2009-12-06 ago elements: more convenient result;
2009-12-06 ago added elements: Interator;
2009-07-04 ago is_open: surrogate sequence is High..Low;
2009-06-16 ago added names, abbrevs;
2009-06-10 ago tuned;
2009-06-10 ago discontinued escaped symbols such as \\<forall> -- only one backslash should be used;
2009-06-09 ago tuned;
2009-06-09 ago more native Scala style;
2009-01-20 ago more general init of Symbol.Interpretation, independent of IsabelleSystem instance;
2008-12-27 ago proper class IsabelleSystem -- no longer static;
2008-12-19 ago removed Ids;
2008-08-26 ago tuned append;
2008-08-25 ago simplified exceptions: use plain error function / RuntimeException;
2008-08-21 ago pattern: proper "." not "[.]"!
2008-08-21 ago recode: proper result for unmatched symbols;
2008-08-21 ago more robust pattern: look at longer matches first, added catch-all case;
2008-08-21 ago read_symbols: proper IsabelleSystem.platform_path;
2008-08-17 ago decode escaped symbols as well;
2008-08-16 ago tuned Recoder;
2008-08-16 ago more private fields;
2008-08-16 ago tuned comments;
2008-08-16 ago use scala.collection.jcl.HashMap, which seems to be more efficient;
2008-08-16 ago reading symbol interpretation tables;
2008-08-15 ago tuned;
2008-08-15 ago Basic support for Isabelle symbols.