version 1.21; 2017-12-08

  * update for context stack changes in Perl 5.23.8

  * update to accommodate PERL_OP_PARENT builds of Perl 5.21.11 or later
    (which is the default from Perl 5.25.1)

  * update for removal of LEX_KNOWNEXT in Perl 5.25.1

  * update test suite to not rely on . in @INC, which is no longer
    necessarily there from Perl 5.25.7

  * use cleaner wrap_op_checker() API to control op checking

version 1.20; 2015-10-21

  * bugfix: avoid some C undefined behaviour from unsequenced side effects
    that in practice bit when using a newer gcc (4.9 rather than 4.7)
    with the parser token stack change in Perl 5.21.9

  * add doc note advising users to prefer the core aliasing facility on
    Perl 5.22

version 1.19; 2015-10-21

  * bugfix: properly maintain op_last when munging ops

  * update for the parser's PL_expect changes in Perl 5.21.4

  * update for op_private stricture in Perl 5.21.4

  * update for sub references directly in stash in Perl 5.21.4

  * update for IS_PADGV()'s limited visibility in Perl 5.21.4

  * update for increased specialness of OP_PUSHMARK in Perl 5.21.6

  * update for distinct PADNAMELIST type in Perl 5.21.7

  * update for multideref optimisation in Perl 5.21.7, by a disgusting
    hack that depends on a flaw in the optimisation (which may disappear
    in the future) and which disables the optimisation entirely

  * add MYMETA.json to .gitignore

version 1.18; 2013-09-21

  * bugfix: store peep chain link reliably under threads

  * update tests for Perl 5.19.4's removal of the special treatment of
    aliased undef in arrays

  * in doc, switch to consistent use of British English spellings

  * doc typo fix

version 1.17; 2013-08-04

  * bugfix: correct the dtrace-related macro squashing for Perls prior
    to 5.13.8, where the macros had the wrong number of parameters and
    prevented compilation

  * bugfix: use core's PL_no_localize_ref string constant as data string
    rather than format string

  * update to handle the new padrange op type in Perl 5.17.6

  * update to handle the new op allocation mechanism in Perl 5.17.2

  * clarify and expand documentation around list-like assignments

  * clarify documentation of deref() regarding lvalueness

  * remove the bulk of the documentation from the README file

version 1.16; 2011-11-17

  * bugfix: use supported API to put destructor calls on the save stack
    (the unsupported way used before was wrong for 64-bit systems on
    perl 5.13.1 and later)

  * document the behaviour of "alias return" in more detail

  * convert .cvsignore to .gitignore

version 1.15; 2011-06-21

  * port to Perl 5.15.0, where the op type aelemfast has been split into
    aelemfast and aelemfast_lex

  * test compatibility with Devel::CallParser

version 1.14; 2011-04-27

  * bugfix: never unhook peephole optimiser, because unhooking is liable
    to fail if anything else hooked it

  * bugfix: revise check for dorassign opcode to cope with FreeBSD's
    mutant Perl 5.8 that has it

  * test POD syntax and coverage

version 1.13; 2011-04-25

  * bugfix: prevent the lexer getting confused if the first thing inside
    an alias{} block is an open paren

  * bugfix: don't crash if an rv2cv op is built with PL_parser null

  * bugfix: handle variant structure of entersub op which lacks (ex-)list
    op as direct child

  * bugfix: squash bogus dtrace-related macro definitions that are picked
    up due to defining PERL_CORE

  * switch all pp functions to internal linkage

  * avoid some compiler warnings

  * include .cvsignore file in distribution

1.12  Tue Feb 22 20:47 GMT 2011
	- Updated to work with Perl version 5.13.10, where GvGP() and
	  GvCV() are not directly-assignable lvalues

1.11  Thu Jan 13 20:23 GMT 2011
	- Don't rely on details of core's pp_* functions to determine
	  whether an opcode exists, because they can change unpredictably
	  (and do change in Perl 5.13.9)

1.10  Sun Nov 21 09:04 GMT 2010
	- Updated to work with Perl version 5.13.7, where lex_end()
	  has disappeared and mod() is now in the public API under the
	  name op_lvalue()

1.09  Mon Nov 15 21:36 GMT 2010
	- Modify source filter test to use Filter::Util::Call directly
	  instead of the deprecated Switch, and to not fail if it is not
	  available, thus allowing tests to pass on Perl versions 5.13.1
	  and above where Switch is no longer in the core distribution
	- Updated to work with Perl version 5.13.6, where global variables
	  are managed in a different way from before

1.08  Fri Oct 22 09:39 BST 2010
	- Updated to work with Perl versions 5.11.0 up to 5.13.0,
	  including particularly the major change in when rv2cv ops get
	  built in 5.11.2

1.07  Mon Sep 10 22:25 CEST 2007
	- Fixed reference miscounting for 'my VAR' inside alias

1.06  Thu Jun 28 22:29 CEST 2007
	- Fixed crash when conditionally aliasing whole aggregate

1.05  Sun May  6 16:36 CEST 2007
	- Updated to work with recent bleadperl (5.9.5 patch 31154)

1.04  Thu May  3 16:17 CEST 2007
	- Avoid directly calling pp_* functions
	- Fixed copy() of empty list in scalar context
	- Updated to work with recent bleadperl (5.9.5 patch 31058)
	- Switched to using Module::Install
	- Added perl version compatibility test on Win32 and AIX

1.03  Fri Mar 16 15:38 CET 2007
	- Updated to work with recent bleadperl (5.9.5 patch 29836)

1.02  Tue Jan  9 16:59 CET 2007
	- Updated to work with recent bleadperl (5.9.5 patch 29570)

1.01  Fri Sep 29 23:39 CEST 2006
	- Worked around perl bug (wrong context of refgen due to prototype)
	- Updated to work with recent bleadperl
	- Warn on aliasing a lexical where the effect is limited in scope
	  (category "closure")

1.0   Mon Jul 12 23:17 CEST 2006
	- Further enhanced performance of alias-assign
	- Fixed compile errors on non-gcc compilers
	- Fixed aliasing a constant expression
	- Don't export "copy" by default anymore
	- Properly reallocate ops (bug exposed by perl 5.9.4 patch 27773)
	- Enhanced performance of copy in void context
	- Alias-refgen properly makes stuff read-only that ought to be
	- Support defined-or-assign (//=) in perl 5.9.x

0.10  Sat Jun  3 17:44 CEST 2006
	- Enhanced performance of alias-assign
	- Made a note about 'local' in the docs

0.09  Mon May 22 17:12 CEST 2006
	- Suppress warnings when using 64-bit integers on 32-bit arch
	- 'local' now doesn't act differently on tied vars than on normal ones
	- Added "Useless use of alias" warning (category 'void')

0.08  Wed Feb  8 20:19 CET 2006
	- Avoid giving the "tied array/hash" error when inappropriate, such
	  as when the array/hash is merely the target of weakrefs

0.07  Mon Feb  6 16:43 CET 2006
	- Removed outer lexical support, since it can't be made to work in
	  any consistent way

0.06  Mon Feb  6 00:35 CET 2006
	- Fixed memory mismanagement bug (crash)
	- Fixed parse failure of 'alias' or 'copy' at EOF

0.05  Wed Jan 25 15:48 CET 2006
	- Split off Data::Swap again
	- Perl 5.9.3 support
	- Fixed alias-returning from within a nested block

0.04  Sun Aug 29 21:01 CEST 2004
	- Minor fix because PAUSE complained about missing version in Data::Swap

0.03  Sun Aug 29 00:36 CEST 2004
	- Initial version of Data::Alias  (incorporates Data::Swap)
	- Fixed swapping objects with weakrefs

0.02  Thu Jul  3 11:34 CEST 2003
	- Added Changes file
	- Disallow swapping an overloaded object with a non-overloaded one

0.01  Mon Jun 30 20:08 CEST 2003
	- Initial version