This file records noteworthy changes.
+1.2.0 (<insert date>)
+* Added a structure<T> template class for the easy creation of user-defined
+ algebraic classes.
+* Added support for (acyclic) visitors, to allow cleaner implementations of
+ algebraic algorithms.
+* <iterators>
+* Completely revamped the implementation of expression output. It is now
+ possible to add new output formats, to change the behavior of predefined
+ formats at run-time, and to have different output styles for algebraic
+ functions.
+* Symbols can be made non-commutative.
+* Improved the speed of subs(), normal(), to_rational() and to_polynomial()
+ by the use of maps instead of lists. The old forms
+ subs(const lst & ls, const lst & lr, unsigned options)
+ to_rational/to_polynomial(lst & repl)
+ are still available for compatibility, but using the new forms
+ subs(const exmap & m, unsigned options)
+ to_rational/to_polynomial(exmap & repl)
+ is more efficient, especially when the number of replacements is large.
+* quo(), rem(), prem(), sprem(), decomp_rational(), unit(), content(),
+ primpart() and matrix::charpoly() now take a "const ex &" instead of a
+ "const symbol &".
+* <object fusion>
+* Lots of internal streamlining and optimizations.
+* Caveats for class implementors:
+ - basic::copy() and basic::destroy() are gone; classes derived from
+ basic can use the defaults for the assignment operator and copy
+ constructor.
+ - basic::subs(), basic::normal(), basic::to_rational() and
+ basic::to_polynomial() take 'exmap' objects instead of lists.
+ - basic::subs() now descends into subexpressions (if accessible via
+ nops()/op()/let_op()). If you have a custom implementation of subs()
+ that calls basic::subs() after substituting subexpressions, this needs
+ to be changed to a call to subs_one_level().
+ - lst::thislst() and exprseq::thisexprseq() renamed to thiscontainer().
+ - thiscontainer() and associated constructors now take a std::auto_ptr.
+ - Overloading basic::print() is now deprecated. You should use
+ print_func<>() class options instead.
+
+1.1.0 (3 April 2003)
+* Removed deprecated macros is_ex_a, is_ex_exactly_a and friends for good.
+* The scalar_products mechanism allows the specification of an index dimension.
+* Removed dirac_gamma6/7().
+* Added ex::to_polynomial().
+* subs() accepts an optional "options" argument. The option
+ subs_option::subs_algebraic enables "smart" substitutions in products and
+ powers.
+* Added stream manipulators "dflt", "latex", "python", "python_repr", "tree",
+ "csrc", "csrc_float", "csrc_double", "csrc_cl_N", "index_dimensions" and
+ "no_index_dimensions" to control the output format. Calling basic::print()
+ directly is now deprecated.
+* Made the hashing more simple and efficient.
+* Caveats for class implementors:
+ - basic::subs(): third argument changed from "bool" to "unsigned"
+ - unarchiving constructor and basic::unarchive(): "const" removed from
+ second argument
+ - basic::let_op() should only be implemented if write access to
+ subexpressions is desired
+ - simplify_ncmul() renamed to eval_ncmul()
+ - simplified_ncmul() renamed to hold_ncmul()
+ - nonsimplified_ncmul() renamed to reeval_ncmul()
+
1.0.14 (1 March 2003)
* Improved the C-source output: complex numbers are printed correctly (using
the STL complex<> template or cln::complex()), rational numbers use cl_RA()