2011-11-09 ago avoid separate typ_check phases, integrate into main term_check 0 instead (cf. its Syntax.check_typs in Type_Infer_Context.prepare);
2011-11-09 ago clarified singleton_fixate: intersection with supersort is identity, only replace actual type inference parameters;
2011-11-09 ago misc tuning and simplification;
2011-11-09 ago tuned signature;
2011-11-09 ago tuned layout;
2011-04-27 ago tuned signature -- eliminated odd comment;
2011-04-19 ago simplified check/uncheck interfaces: result comparison is hardwired by default;
2011-04-17 ago report Name_Space.declare/define, relatively to context;
2011-04-16 ago modernized structure Proof_Context;
2011-04-16 ago tuned signature, disentangled dependencies;
2011-01-16 ago added before_exit continuation for named targets (locale, class etc.), e.g. for final check/cleanup as in VC management;
2010-10-26 ago consider base sorts of superclasses simultaneously during processing of class specification -- avoids clash of different base sorts
2010-08-30 ago tuned messages: discontinued spurious full-stops (messages are occasionally composed unexpectedly);
2010-08-26 ago renamed ProofContext.theory(_result) to ProofContext.background_theory(_result) to emphasize that this belongs to the infrastructure and is rarely appropriate in user-space tools;
2010-08-17 ago enforcing a singleton type inference parameter after type inference and before fixation prevents multiple type variables in import during class declaration
2010-08-13 ago corrected handling of `constrains` elements
2010-08-12 ago named target is optional
2010-08-12 ago Named_Target.init: empty string represents theory target
2010-08-11 ago merged
2010-08-11 ago more convenient split of class modules: class and class_declaration