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express, and easier for a human to look at and understand, and finally
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easier to manage. The oldest version with which the API for a python
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object is compatible is obtained by looking up the ``api_minimum_version``
50
attribute on the python object handed to ``require_api``. The current
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version of the API is obtained by looking for an ``api_current_version``
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attribute, and if that is not found, an ``version_info`` attribute (of
53
which the first 3 elements are used). If no current version can be found,
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the bzrlib ``version_info`` attribute is used to generate a current API
55
version. API versions are compared lexically to answer the question 'is
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attribute on the python object handed to ``require_api``, and failing that
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the bzrlib ``api_minimum_version`` is returned. The current version of the
52
API is obtained by looking for an ``api_current_version`` attribute, and
53
if that is not found, an ``version_info`` attribute (of which the first 3
54
elements are used). If no current version can be found, the bzrlib
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``version_info`` attribute is used to generate a current API version.
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This lookup sequence allows users with simple setups (and no python style
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``version_info`` tuple) to still export an API version, and for new API's
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to be managed more granularly later on with a smooth transition -
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everything starts off in lockstep with bzrlib's master version.
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API versions are compared lexically to answer the question 'is
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the requested version X <= the current version, and >= the minimum
added
removed
doc/developers/api-versioning.txt
