#217 (Jun 1, 2016, 8:26:08 PM)

1. merged (detail / hgweb)
2. NEWS; (detail / hgweb)
3. more adhoc overloading;
   eliminated pointless Rat.eq: this is an equality type;
   tuned; (detail / hgweb)
4. clarified exception -- actually reject denominator = 0; (detail / hgweb)
5. ML pp for Rat.rat; (detail / hgweb)
6. clarified string_of_rat operations; (detail / hgweb)
7. tuned signature; (detail / hgweb)
8. clarified signature; (detail / hgweb)
9. prefer rat numberals; (detail / hgweb)
10. support rat numerals via special antiquotation syntax; (detail / hgweb)
11. tuned signature; (detail / hgweb)
12. tuned; (detail / hgweb)
13. tuned signature; (detail / hgweb)
14. maintain invariant for exported operation; (detail / hgweb)
15. prefer more efficient Poly/ML operations, taking care of sign; (detail / hgweb)
16. ad-hoc overloading for standard operations on type Rat.rat; (detail / hgweb)
17. rat.ML is now part of Pure to allow tigther integration with Isabelle/ML; (detail / hgweb)

Started by an SCM change