Revision history for Perl extension Heap::Simple.

Plan:
  - Deleting
  - return undef on underflow if requested
  - Tied interface
  - Special handling for duplicate keys (error, share, overwrite, separate)
  - add a callback for elements lost in max_count overflow

0.07
        - Split off Heap::Simple to its own package. This package is now
          Heap::Simple::Perl
        - Add a "top" method.
	- Use the "official" constant for infinity (9**9**9)
        - Expand array, hash and method keys inplace (if safe)
        - Check for unknown options
	- Generate code in proper package and with proper name
	  (defining a function twice is now a redefine warning)
        - _make substitutions functions must start with _, not just contain it
	- drop the (always undocumented) internal _init method.
	  It was too awkward to use anyways.
        - Move perl code to Simple/Perl.pm in preparation for an XS switch
	- Renamed the "Key" element type to "Scalar". "Key" remains supported
          for backward compatibility.
	- Consistent error message for getting an element of an empty heap.
        - Document that the methods that return undef on empty are only
          guaranteed to do so in scalar context.
        - Added an extract_first method that returns nothing on empty.
	- Replace test suite with a much cleaner one
        - More fair speed testing
        - Added speed compare with Array::Heap2
	- Added "wrapped", "order" and "elements" methods.
        - Make index 0 into a hash now that more and more attributes get added
	- Save and restore $@ around _make() based code creation.

0.06  2004-09-29
        - Don't scare away users by directly explaining all possibilities in
          the docs. Add examples to the top to show basic usage.
        - Fix author email.
        - Be paranoid about defining an expanded function twice.
        - Rename extract_min to extract_top (like Heap did). Keep
          extract_min around for backward compatibility. Same with top_key
          (used to be min_key)
        - Move Simple.pm into lib/Heap
        - Allow Simple.pm and package version to be different

0.05  2003-05-20
        - reorder s.t to take much less memory (failed on fast machines with
          little memory).
        - Added keys, values and clear methods, with tests and documentation

0.04  2003-05-19
        - Small documentation changes
        - Bugfix: "Any" and "Object" element types without arguments failed

0.03  2003-05-19
        - Added settable infinity
        - Added generic compare function
        - min_key now always exists, but can fail on empty heaps
        - reordered $self->[0] from most to least likely
        - Added the Object and Any element methods
        - Added testcases for element methods Method, Object, Function and Any
        - Added method "key_insert"
        - Added testcases for generic compare
        - Added method "key"
        - Documented all new stuff
        - Reduce the number of tests. Still way too many though.

0.02  2003-05-15
        - Added testcases for > and gt
        - Cleaned up the tests a bit
        - Do a bit less work in the tests (faster)
        - autocalibrate the big benchmark test.
        - Unify n.t and s.t. Only run the number variant by default.
        - Unify 2.t into 1.t
        - changed the macro-expander so it supports balanced parenthesis
        - Added the Method and Function element types for completely general
          key fetching (not documented or tested yet)

0.01  2003-05-14
	- original version; created by h2xs 1.22 with options
		-X -n Heap::Simple
        - Insert code from my old FastHeap module
        - Slight code changes
        - Make special versions (Plain, Array, Hash)
        - add testcases
        - Prepare for release
        - Module set too simular, names too confusing. Refactor module names
          into arguments.
        - remove perl 5.6 dependencies (untested)
        - Prepare for release again.