
.. This document was originally written by Richard Boulton.

.. Copyright (C) 2007 Lemur Consulting Ltd
.. Copyright (C) 2007,2008,2009,2010,2011,2012,2013,2015,2016 Olly Betts

===========
Deprecation
===========

.. contents:: Table of contents

Introduction
============

Xapian's API is fairly stable and has been polished piece by piece over time,
but it still occasionally needs to be changed.  This may be because a new
feature has been implemented and the interface needs to allow access to it, but
it may also be required in order to polish a rough edge which has been missed
in earlier versions of Xapian, or simply to reflect an internal change which
requires a modification to the external interface.

We aim to make such changes in a way that allows developers to work against a
stable API, while avoiding the need for the Xapian developers to maintain too
many old historical interface artefacts.  This document describes the process
we use to deprecate old pieces of the API, lists parts of the API which are
currently marked as deprecated, and also describes parts of the API which have
been deprecated for some time, and are now removed from the Xapian library.

It is possible for functions, methods, constants, types or even whole classes
to be deprecated, but to save words this document will often use the term
"features" to refer collectively to any of these types of interface items.


Deprecation Procedure
=====================

Deprecation markers
-------------------

At any particular point, some parts of the C++ API will be marked as
"deprecated".  Deprecated features are annotated in the API headers with macros
such as ``XAPIAN_DEPRECATED()``, which will cause compilers with appropriate
support (such as GCC, clang and MSVC) to emit compile-time warnings if these
features are used.

If a feature is marked with one of these markers, you should avoid using it in
new code, and should migrate your code to use a replacement when possible.  The
documentation comments for the feature, or the list at the end
of this file, will describe possible alternatives to the deprecated feature.

If you want to disable deprecation warnings temporarily, you can do so
by passing ``"-DXAPIAN_DEPRECATED(X)=X"`` to the compiler (the quotes are
needed to protect the brackets from the shell).  If your build system uses
make, you might do this like so:

.. code-block:: sh

    make 'CPPFLAGS="-DXAPIAN_DEPRECATED(X)=X"'

API and ABI compatibility
-------------------------

Releases are given three-part version numbers (e.g. 1.2.9), the three parts
being termed "major" (1), "minor" (2), and "revision" (9).  Releases with
the same major and minor version are termed a "release series".

For Xapian releases 1.0.0 and higher, an even minor version indicates a stable
release series, while an odd minor version indicates a development release
series.

Within a stable release series, we strive to maintain API and ABI forwards
compatibility.  This means that an application written and compiled against
version `X.Y.a` of Xapian should work, without any source changes or need to
recompile, with a later version `X.Y.b`, for all `b` >= `a`.
Stable releases which increase the minor or major version number will usually
change the ABI incompatibly (so that code will need to be recompiled against
the newer release series.  They may also make incompatible API changes,
though we will attempt to do this in a way which makes it reasonably easy to
migrate applications, and document how to do so in this document.

It is possible that a feature may be marked as deprecated within a minor
release series - that is from version `X.Y.c`
onwards, where `c` is not zero.  The API and ABI will not be changed by this
deprecation, since the feature will still be available in the API (though the
change may cause the compiler to emit new warnings when rebuilding code
which uses the now-deprecated feature).

Users should generally be able to expect working code which uses Xapian not to
stop working without reason.  We attempt to codify this in the following
policy, but we reserve the right not to slavishly follow this.  The spirit of
the rule should kept in mind - for example if we discovered a feature which
didn't actually work, making an incompatible API change at the next ABI bump
would be reasonable.

Normally a feature will be supported after being deprecated for an entire
stable release series.  For example, if a feature is deprecated in release
1.2.0, it will be supported for the entire 1.2.x release series, and removed in
development release 1.3.0.  If a feature is deprecated in release 1.2.1, it
will be supported for the 1.2.x *and* 1.4.x stable release series (and of
course the 1.3.x release series in between), and won't be removed until
1.5.0.

Experimental features
---------------------

During a development release series (such as the 1.1.x series), some features
may be marked as "experimental".  Such features are liable to change without
going through the normal deprecation procedure.  This includes changing on-disk
formats for data stored by the feature, and breaking API and ABI compatibility
between releases for the feature.  Such features are included in releases to
get wider use and corresponding feedback about them.

Deprecation in the bindings
---------------------------

When the Xapian API changes, the interface provided by the Xapian bindings will
usually change in step.  In addition, it is sometimes necessary to change the
way in which Xapian is wrapped by bindings - for example, to provide a better
convenience wrapper for iterators in Python.  Again, we aim to ensure that an
application written (and compiled, if the language being bound is a compiled
language) for version `X.Y.a` of Xapian should work without any changes or need
to recompile, with a later version `X.Y.b`, for all `a` <= `b`.

However, the bindings are a little less mature than the core C++ API, so we
don't intend to give the same guarantee that a feature present and not
deprecated in version `X.Y.a` will work in all versions `X+1.Y.b`.  In other
words, we may remove features which have been deprecated without waiting for
an entire release series to pass.

Any planned deprecations will be documented in the list of deprecations and
removed features at the end of this file.

Support for Other Software
==========================

Support for other software doesn't follow the same deprecation rules as
for API features.

Our guiding principle for supporting version of other software is that
we don't aim to actively support versions which are no longer supported
"upstream".

So Xapian 1.1.0 doesn't support PHP4 because the PHP team no longer did
when it was released.  By the API deprecation rules we should have announced
this when Xapian 1.0.0 was released, but we don't have control over when and
to what timescales other software providers discontinue support for older
versions.

Sometimes we can support such versions without extra effort (e.g. Tcl's
stubs mechanism means Tcl 8.1 probably still works, even though the last
8.1.x release was over a decade ago), and in some cases Linux distros
continue to support software after upstream stops.

But in most cases keeping support around is a maintenance overhead and
we'd rather spend our time on more useful things.

Note that there's no guarantee that we will support and continue to
support versions just because upstream still does.  For example, we ceased
providing backported packages for Ubuntu dapper with Xapian 1.1.0 - in this
case, it's because we felt that if you're conservative enough to run dapper,
you'd probably prefer to stick with 1.0.x until you upgrade to hardy (the next
Ubuntu LTS release).  But we may decide not to support versions for other
reasons too.

How to avoid using deprecated features
======================================

We recommend taking the following steps to avoid depending on deprecated
features when writing your applications:

 - If at all possible, test compile your project using a compiler which
   supports warnings about deprecated features (such as GCC 3.1 or later), and
   check for such warnings.  Use the -Werror flag to GCC to ensure that you
   don't miss any of them.

 - Check the NEWS file for each new release for details of any new features
   which are deprecated in the release.

 - Check the documentation comments, or the automatically extracted API
   documentation, for each feature you use in your application.  This
   documentation will indicate features which are deprecated, or planned for
   deprecation.

 - For applications which are not written in C++, there is currently no
   equivalent of the ``XAPIAN_DEPRECATED`` macro for the bindings, and thus
   there is no way for the bindings to give a warning if a deprecated feature
   is used.  This would be a nice addition for those languages in which there
   is a reasonable way to give such warnings.  Until such a feature is
   implemented, all application writers using the bindings can do is to check
   the list of deprecated features in each new release, or lookup the features
   they are using in the list at the end of this file.


Features currently marked for deprecation
=========================================

Native C++ API
--------------

.. Substitution definitions for feature names which are two wide for the column:

.. |set_max_wildcard_expansion| replace:: ``Xapian::QueryParser::set_max_wildcard_expansion()``
.. |flush| replace:: ``Xapian::WritableDatabase::flush()``
.. |VRP| replace:: ``Xapian::ValueRangeProcessor``
.. |DateVRP| replace:: ``Xapian::DateValueRangeProcessor``
.. |NumberVRP| replace:: ``Xapian::NumberValueRangeProcessor``
.. |StringVRP| replace:: ``Xapian::StringValueRangeProcessor``
.. |add_valuerangeprocessor| replace:: ``Xapian::QueryParser::add_valuerangeprocessor()``

.. Keep table width to <= 126 columns.

========== ====== =================================== ========================================================================
Deprecated Remove Feature name                        Upgrade suggestion and comments
========== ====== =================================== ========================================================================
1.3.0      1.5.0  ``Xapian::timeout`` typedef         Use ``unsigned`` instead, which should also work with older Xapian
                                                      releases.
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.0      1.5.0  ``Xapian::percent`` typedef         Use ``int`` instead, which should also work with older Xapian releases.
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.0      1.5.0  ``Xapian::weight`` typedef          Use ``double`` instead, which should also work with older Xapian
                                                      releases.
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.1      1.5.0  ``Xapian::ErrorHandler``            We feel the current ErrorHandler API doesn't work at the right level (it
                                                      only works in Enquire, whereas you should be able to handle errors at
                                                      the Database level too) and we can't find any evidence that people are
                                                      actually using it.  So we've made the API a no-op and marked it as
                                                      deprecated.  The hope is to replace it with something better thought
                                                      out, probably during the 1.4.x release series.  There's some further
                                                      thoughts at https://trac.xapian.org/ticket/3#comment:8
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.2      1.5.0  ``Xapian::Auto::open_stub()``       Use the constructor with ``Xapian::DB_BACKEND_STUB`` flag (new in 1.3.2)
                                                      instead.
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.2      1.5.0  ``Xapian::Chert::open()``           Use the constructor with ``Xapian::DB_BACKEND_CHERT`` flag (new in
                                                      1.3.2) instead.
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.2      1.5.0  ``Xapian::Enquire::get_eset()``     Use ``Xapian::Enquire::set_expansion_scheme()`` to specify the algorithm
                  overloaded form taking ``k``        which ``get_eset()`` should use, along with any parameters (added in
                  parameter.                          1.3.2).
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.3      1.5.0  |set_max_wildcard_expansion|        Use ``Xapian::QueryParser::set_max_expansion()`` instead.
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.4      1.5.0  ``Xapian::Compactor`` methods       Use the ``Xapian::Database::compact()`` method instead.  The
                  ``set_block_size()``,               ``Xapian::Compactor`` class is now just a subclassable functor class to
                  ``set_renumber()``,                 allow access to progress messages and control over merging of user
                  ``set_multipass()``,                metadata.
                  ``set_compaction_level()``,
                  ``set_destdir()``, ``add_source()`
                  and ``compact()``.
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.5      1.5.0  ``Xapian::ValuePostingSource``      Use the respective getter and setter methods instead, added in 1.3.5 and
                  public member variables             1.2.23.
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.5      1.5.0  ``Xapian::InMemory::open()``        Use the constructor with ``Xapian::DB_BACKEND_INMEMORY`` flag (new in
                                                      1.3.5) instead.
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.6      1.5.0  |flush|                             Use ``Xapian::WritableDatabase::commit()`` instead (available since
                                                      1.1.0).
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.6      1.5.0  Subclassing |VRP|                   Subclass ``Xapian::RangeProcessor`` instead, and return a
                                                      ``Xapian::Query`` from ``operator()()`` (added in 1.3.6).
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.6      1.5.0  |DateVRP|                           Use ``Xapian::DateRangeProcessor`` instead (added in 1.3.6).
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.6      1.5.0  |NumberVRP|                         Use ``Xapian::NumberRangeProcessor`` instead (added in 1.3.6).
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.6      1.5.0  |StringVRP|                         Use ``Xapian::RangeProcessor`` instead, which includes equivalent
                                                      support for prefix/suffix checking (added in 1.3.6).
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.3.6      1.5.0  |add_valuerangeprocessor|           Use ``Xapian::QueryParser::add_rangeprocessor()`` instead, with a
                                                      ``Xapian::RangeProcessor`` object instead of a |VRP| object (added in
                                                      1.3.6).
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.4.11     1.7.0  Environment variable                Specify via the flags ``Xapian::QueryParser::FLAG_CJK_NGRAM``,
                  ``XAPIAN_CJK_NGRAM``                ``Xapian::TermGenerator::FLAG_CJK_NGRAM`` and
                                                      ``Xapian::MSet::SNIPPET_CJK_NGRAM`` instead.
========== ====== =================================== ========================================================================

Bindings
--------

.. Keep table width to <= 126 columns.

========== ====== ======== ============================ ======================================================================
Deprecated Remove Language Feature name                 Upgrade suggestion and comments
========== ====== ======== ============================ ======================================================================
1.2.5      1.5.0  Python   MSet.items                   Iterate the MSet object itself instead.
---------- ------ -------- ---------------------------- ----------------------------------------------------------------------
1.2.5      1.5.0  Python   ESet.items                   Iterate the ESet object itself instead.
========== ====== ======== ============================ ======================================================================

Omega
-----

.. Keep table width to <= 126 columns.

========== ====== =================================== ========================================================================
Deprecated Remove Feature name                        Upgrade suggestion and comments
========== ====== =================================== ========================================================================
1.2.4      1.5.0  omindex command line long option    Renamed to ``--no-delete``, which works in 1.2.4 and later.
                  ``--preserve-nonduplicates``.
---------- ------ ----------------------------------- ------------------------------------------------------------------------
1.2.5      1.5.0  $set{spelling,true}                 Use $set{flag_spelling_suggestion,true} instead.
========== ====== =================================== ========================================================================

.. Features currently marked as experimental
.. =========================================
.. Native C++ API
.. --------------
.. ============== ===============================================================================================================
.. Name           Details
.. ============== ===============================================================================================================
.. -------------- ---------------------------------------------------------------------------------------------------------------
.. ============== ===============================================================================================================

Features removed from Xapian
============================

Native C++ API
--------------

.. Keep table width to <= 126 columns.

======= =================================== ==================================================================================
Removed Feature name                        Upgrade suggestion and comments
======= =================================== ==================================================================================
1.0.0   QueryParser::set_stemming_options() Use ``set_stemmer()``, ``set_stemming_strategy()`` and/or ``set_stopper()``
                                            instead:

                                            - ``set_stemming_options("")`` becomes
                                              ``set_stemming_strategy(Xapian::QueryParser::STEM_NONE)``

                                            - ``set_stemming_options("none")`` becomes
                                              ``set_stemming_strategy(Xapian::QueryParser::STEM_NONE)``

                                            - ``set_stemming_options(LANG)`` becomes
                                              ``set_stemmer(Xapian::Stem(LANG)`` and
                                              ``set_stemming_strategy(Xapian::QueryParser::STEM_SOME)``

                                            - ``set_stemming_options(LANG, false)`` becomes
                                              ``set_stemmer(Xapian::Stem(LANG)`` and
                                              ``set_stemming_strategy(Xapian::QueryParser::STEM_SOME)``

                                            - ``set_stemming_options(LANG, true)`` becomes
                                              ``set_stemmer(Xapian::Stem(LANG)`` and
                                              ``set_stemming_strategy(Xapian::QueryParser::STEM_ALL)``

                                            If a third parameter is passed, ``set_stopper(PARAM3)`` and treat the first two
                                            parameters as above.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   Enquire::set_sort_forward()         Use ``Enquire::set_docid_order()`` instead:

                                             - ``set_sort_forward(true)`` becomes ``set_docid_order(ASCENDING)``
                                             - ``set_sort_forward(false)`` becomes ``set_docid_order(DESCENDING)``
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   Enquire::set_sorting()              Use ``Enquire::set_sort_by_relevance()``, ``Enquire::set_sort_by_value()``, or
                                            ``Enquire::set_sort_by_value_then_relevance()`` instead.

                                             - ``set_sorting(KEY, 1)`` becomes ``set_sort_by_value(KEY)``
                                             - ``set_sorting(KEY, 1, false)`` becomes ``set_sort_by_value(KEY)``
                                             - ``set_sorting(KEY, 1, true)`` becomes ``set_sort_by_value_then_relevance(KEY)``
                                             - ``set_sorting(ANYTHING, 0)`` becomes ``set_sort_by_relevance()``
                                             - ``set_sorting(Xapian::BAD_VALUENO, ANYTHING)`` becomes
                                               ``set_sort_by_relevance()``
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   Stem::stem_word(word)               Use ``Stem::operator()(word)`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   Auto::open(path)                    Use the ``Database(path)`` constructor instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   Auto::open(path, action)            Use the ``WritableDatabase(path, action)`` constructor instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   Query::is_empty()                   Use ``Query::empty()`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   Document::add_term_nopos()          Use ``Document::add_term()`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   Enquire::set_bias()                 Use ``PostingSource`` instead (new in 1.2).
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   ExpandDecider::operator()           Return type is now ``bool`` not ``int``.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   MatchDecider::operator()            Return type is now ``bool`` not ``int``.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   Error::get_type()                   Return type is now ``const char *`` not ``std::string``.  Most existing code
                                            won't need changes, but if it does the simplest fix is to write
                                            ``std::string(e.get_type())`` instead of ``e.get_type()``.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   <xapian/output.h>                   Use ``cout << obj.get_description();`` instead of ``cout << obj;``
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   Several constructors marked         Explicitly create the object type required, for example use
        as explicit.                        ``Xapian::Enquire enq(Xapian::Database(path));`` instead of
                                            ``Xapian::Enquire enq(path);``
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   QueryParser::parse_query() throwing Catch ``Xapian::QueryParserError`` instead of ``const char *``, and call
        ``const char *`` exception.         ``get_msg()`` on the caught object.  If you need to build with either version,
                                            catch both (you'll need to compile the part which catches ``QueryParserError``
                                            conditionally, since this exception isn't present in the 0.9 release series).
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   xapian_version_string()             Use ``version_string()`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   xapian_major_version()              Use ``major_version()`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   xapian_minor_version()              Use ``minor_version()`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   xapian_revision()                   Use ``revision()`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   Enquire::include_query_terms        Use ``Enquire::INCLUDE_QUERY_TERMS`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   Enquire::use_exact_termfreq         Use ``Enquire::USE_EXACT_TERMFREQ`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   Error::get_errno()                  Use ``Error::get_error_string()`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   Enquire::register_match_decider()   This method didn't do anything, so just remove calls to it!
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   Query::Query(Query::op, Query)      This constructor isn't useful for any currently implemented
                                            ``Query::op``.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   The Quartz backend                  Use the Chert backend instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   Quartz::open()                      Use ``Chert::open()`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   quartzcheck                         Use ``xapian-check`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   quartzcompact                       Use ``xapian-compact`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   quartzdump                          Use ``xapian-inspect`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   configure --enable-debug            configure --enable-assertions
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   configure --enable-debug=full       configure --enable-assertions --enable-log
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   configure --enable-debug=partial    configure --enable-assertions=partial
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   configure --enable-debug=profile    configure --enable-log=profile
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   configure --enable-debug-verbose    configure --enable-log
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   ``Database::positionlist_begin()``  This check is quite expensive, and often you don't care.  If you
        throwing ``RangeError`` if the      do it's easy to check - just open a ``TermListIterator`` for the
        term specified doesn't index the    document and use ``skip_to()`` to check if the term is there.
        document specified.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   ``Database::positionlist_begin()``  This check is quite expensive, and often you don't care.  If you
        throwing ``DocNotFoundError`` if    do, it's easy to check - just call ``Database::get_document()`` with the
        the document specified doesn't      specified document ID.
        exist.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.5   delve -k                            Accepted as an undocumented alias for -V since 0.9.10 for compatibility with 0.9.9
                                            and earlier.  Just use -V instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.0   The Flint backend                   Use the Chert backend instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.0   Flint::open()                       Use ``Chert::open()`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.0   xapian-chert-update                 Install Xapian 1.2.x (where x >= 5) to update chert databases from 1.1.3 and
                                            earlier.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.0   Default second parameter to         The parameter name was ``ascending`` and defaulted to ``true``.  However
        ``Enquire`` sorting functions.      ascending=false gave what you'd expect the default sort order to be (and probably
                                            think of as ascending) while ascending=true gave the reverse (descending) order.
                                            For sanity, we renamed the parameter to ``reverse`` and deprecated the default
                                            value.  In the more distant future, we'll probably add a default again, but of
                                            ``false`` instead.

                                            The methods affected are:
                                            ``Enquire::set_sort_by_value(Xapian::valueno sort_key)``
                                            ``Enquire::set_sort_by_key(Xapian::Sorter * sorter)``
                                            ``Enquire::set_sort_by_value_then_relevance(Xapian::valueno sort_key)``
                                            ``Enquire::set_sort_by_key_then_relevance(Xapian::Sorter * sorter)``
                                            ``Enquire::set_sort_by_relevance_then_value(Xapian::valueno sort_key)``
                                            ``Enquire::set_sort_by_relevance_then_key(Xapian::Sorter * sorter)``

                                            To update them, just add a second parameter with value ``true`` to each of the
                                            above calls.  For the methods which take a ``Xapian::Sorter`` object, you'll also
                                            need to migrate to ``Xapian::KeyMaker`` (see below).
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.0   ``Sorter`` abstract base class.     Use ``KeyMaker`` class instead, which has the same semantics, but has been renamed
                                            to indicate that the keys produced may be used for purposes other than sorting (we
                                            plan to allow collapsing on generated keys in the future).
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.0   ``MultiValueSorter`` class.         Use ``MultiValueKeyMaker`` class instead.  Note that ``MultiValueSorter::add()``
                                            becomes ``MultiValueKeyMaker::add_value()``, but the sense of the direction flag
                                            is reversed (to be consistent with ``Enquire::set_sort_by_value()``), so::

                                                MultiValueSorter sorter;
                                                // Primary ordering is forwards on value 4.
                                                sorter.add(4);
                                                // Secondary ordering is reverse on value 5.
                                                sorter.add(5, false);

                                            becomes::

                                                MultiValueKeyMaker sorter;
                                                // Primary ordering is forwards on value 4.
                                                sorter.add_value(4);
                                                // Secondary ordering is reverse on value 5.
                                                sorter.add_value(5, true);
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.0   ``matchspy`` parameter to           Use the newer ``MatchSpy`` class and ``Enquire::add_matchspy()`` method instead.
        ``Enquire::get_mset()``
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.0   ``Xapian::Query::unserialise()``    To be compatible with older and newer Xapian, you can catch both exceptions.
        throws
        ``Xapian::SerialisationError`` not
        ``Xapian::InvalidArgumentError``
        for errors in serialised data
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.2   The Brass backend                   Use the Glass backend instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.2   ``Xapian::Brass::open()``           Use the constructor with ``Xapian::DB_BACKEND_GLASS`` flag (new in 1.3.2) instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.4   Copy constructors and assignment    We think it was a mistake that implicit copy constructors and assignment operators
        operators for classes:              were being provided for these functor classes - it's hard to use them correctly,
        ``Xapian::ExpandDecider``,          but easy to use them in ways which compile but don't work correctly, and we doubt
        ``Xapian::FieldProcessor`` (new in  anyone is intentionally using them, so we've simply removed them.  For more
        1.3.1), ``Xapian::KeyMaker``,       information, see https://trac.xapian.org/ticket/681
        ``Xapian::MatchDecider``,
        ``Xapian::StemImplementation``,
        ``Xapian::Stopper`` and
        ``Xapian::ValueRangeProcessor``.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.5   ``Xapian::DBCHECK_SHOW_BITMAP``     Use ``Xapian::DBCHECK_SHOW_FREELIST`` (added in 1.3.2) instead.
                                            ``Xapian::DBCHECK_SHOW_BITMAP`` was added in 1.3.0, so has never been in a stable
                                            release.
======= =================================== ==================================================================================


Bindings
--------

.. Keep table width to <= 126 columns.

======= ======== ============================ ================================================================================
Removed Language Feature name                 Upgrade suggestion and comments
======= ======== ============================ ================================================================================
1.0.0   SWIG     Enquire::set_sort_forward()  Use ``Enquire::set_docid_order()`` instead.
        [#rswg]_
                                                - ``set_sort_forward(true)`` becomes ``set_docid_order(ASCENDING)``
                                                - ``set_sort_forward(false)`` becomes ``set_docid_order(DESCENDING)``
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.0.0   SWIG     Enquire::set_sorting()       Use ``Enquire::set_sort_by_relevance()``, ``Enquire::set_sort_by_value()``
        [#rswg]_                              or ``Enquire::set_sort_by_value_then_relevance()`` instead.

                                               - ``set_sorting(KEY, 1)`` becomes ``set_sort_by_value(KEY)``
                                               - ``set_sorting(KEY, 1, false) becomes ``set_sort_by_value(KEY)``
                                               - ``set_sorting(KEY, 1, true)`` becomes
                                                 ``set_sort_by_value_then_relevance(KEY)``
                                               - ``set_sorting(ANYTHING, 0) becomes set_sort_by_relevance()``
                                               - ``set_sorting(Xapian::BAD_VALUENO, ANYTHING)`` becomes
                                                 ``set_sort_by_relevance()``
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.0.0   SWIG     Auto::open(path)             Use the ``Database(path)`` constructor instead.
        [#rswg]_

------- -------- ---------------------------- --------------------------------------------------------------------------------
1.0.0   SWIG     Auto::open(path, action)     Use the ``WritableDatabase(path, action)`` constructor instead.
        [#rswg]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.0.0   SWIG     MSet::is_empty()             Use ``MSet::empty()`` instead.
        [#rsw3]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.0.0   SWIG     ESet::is_empty()             Use ``ESet::empty()`` instead.
        [#rsw3]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.0.0   SWIG     RSet::is_empty()             Use ``RSet::empty()`` instead.
        [#rsw3]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.0.0   SWIG     Query::is_empty()            Use ``Query::empty()`` instead.
        [#rsw3]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.0.0   SWIG     Document::add_term_nopos()   Use ``Document::add_term()`` instead.
        [#rswg]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.0.0   CSharp   ExpandDecider::Apply()       Return type is now ``bool`` instead of ``int``.
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.0.0   CSharp   MatchDecider::Apply()        Return type is now ``bool`` instead of ``int``.
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.0.0   SWIG     Stem::stem_word(word)        Use ``Stem::operator()(word)`` instead. [#callable]_
        [#rswg]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.1.0   SWIG     xapian_version_string()      Use ``version_string()`` instead.
        [#rswg]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.1.0   SWIG     xapian_major_version()       Use ``major_version()`` instead.
        [#rswg]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.1.0   SWIG     xapian_minor_version()       Use ``minor_version()`` instead.
        [#rswg]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.1.0   SWIG     xapian_revision()            Use ``revision()`` instead.
        [#rswg]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.1.0   SWIG     ESetIterator::get_termname() Use ``ESetIterator::get_term()`` instead.  This change is intended to
        [#rswg]_                              bring the ESet iterators in line with other term iterators, which all
                                              support ``get_term()`` instead of ``get_termname()``.

------- -------- ---------------------------- --------------------------------------------------------------------------------
1.1.0   Python   get_description()            All ``get_description()`` methods have been renamed to ``__str__()``,
                                              so the normal python ``str()`` function can be used.
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.1.0   Python   MSetItem.get_*()             All these methods are deprecated, in favour of properties.
                                              To convert, just change ``msetitem.get_FOO()`` to ``msetitem.FOO``
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.1.0   Python   Enquire.get_matching_terms   Replaced by ``Enquire.matching_terms``, for consistency with
                                              rest of Python API.  Note: an ``Enquire.get_matching_terms`` method existed in
                                              releases up-to and including 1.2.4, but this was actually an old implementation
                                              which only accepted a MSetIterator as a parameter, and would have failed with
                                              code written expecting the version in 1.0.0.  It was fully removed after
                                              release 1.2.4.
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.1.0   SWIG     Error::get_errno()           Use ``Error::get_error_string()`` instead.
        [#rswg]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.1.0   SWIG     MSet::get_document_id()      Use ``MSet::get_docid()`` instead.
        [#rsw2]_
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.2.0   Python   mset[i][xapian.MSET_DID] etc This was inadvertently removed in 1.2.0, but not noticed until 1.2.5, by which
                                              point it no longer seemed worthwhile to reinstate it.  Please use the property
                                              API instead, e.g. ``mset[i].docid``, ``mset[i].weight``, etc.
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.2.5   Python   if idx in mset               This was nominally implemented, but never actually worked.  Since nobody seems
                                              to have noticed in 3.5 years, we just removed it.  If you have uses (which were
                                              presumably never called), you can replace them with:
                                              ``if idx >= 0 and idx < len(mset)``
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.3.0   Python   Non-pythonic iterators       Use the pythonic iterators instead.
------- -------- ---------------------------- --------------------------------------------------------------------------------
1.3.0   Python   Stem_get_available_languages Use Stem.get_available_languages instead (static method instead of function)
======= ======== ============================ ================================================================================

.. [#rswg] This affects all SWIG generated bindings (currently: Python, PHP, Ruby, Tcl8 and CSharp)

.. [#rsw2] This affects all SWIG-generated bindings except those for Ruby, support for which was added after the function was deprecated in Xapian-core.

.. [#rsw3] This affects all SWIG generated bindings except those for Ruby, which was added after the function was deprecated in Xapian-core, and PHP, where empty is a reserved word (and therefore, the method remains "is_empty").

.. [#callable] Python handles this like C++.  Ruby renames it to 'call' (idiomatic Ruby).  PHP renames it to 'apply'.  CSharp to 'Apply' (delegates could probably be used to provide C++-like functor syntax, but that's effort and it seems debatable if it would actually be more natural to a C# programmer).  Tcl8 renames it to 'apply' - need to ask a Tcl type if that's the best solution.

Omega
-----

.. Keep table width to <= 126 columns.

======= =================================== ==================================================================================
Removed Feature name                        Upgrade suggestion and comments
======= =================================== ==================================================================================
1.0.0   $freqs                              Use ``$map{$queryterms,$_:&nbsp;$nice{$freq{$_}}}`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   scriptindex -u                      ``-u`` was ignored for compatibility with 0.7.5 and earlier, so just remove it.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.0.0   scriptindex -q                      ``-q`` was ignored for compatibility with 0.6.1 and earlier, so just remove it.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.1.0   scriptindex index=nopos             Use ``indexnopos`` instead.
------- ----------------------------------- ----------------------------------------------------------------------------------
1.3.0   ``OLDP`` CGI parameter              Use ``xP`` CGI parameter instead (direct replacement), which has been supported
                                            since at least 0.5.0.
======= =================================== ==================================================================================
