add Obsoleted-By

pep-0426.txt

@@ -24,11 +24,10 @@ Version 1.1 is specified in PEP 314.
 Version 1.2 is specified in PEP 345.
 
 Version 1.3 of the metadata format adds fields designed to make
-third-party packaging of Python Software easier and defines a
-formal extension mechanism.  The fields are "Setup-Requires-Dist"
-"Provides-Extra", and "Extension".  This version also adds the `extra`
-variable to the `environment markers` specification and allows the
-description to be placed into a payload section.
+third-party packaging of Python Software easier and defines a formal
+extension mechanism.  This version also adds the `extra` variable to the
+`environment markers` specification and allows the description to be
+placed into a payload section.
 
 Metadata Files
 ==============
@@ -354,24 +353,23 @@ Examples::
     Provides-Dist: virtual_package
 
 
-Obsoletes-Dist (multiple use)
-:::::::::::::::::::::::::::::
+Obsoleted-By (optional)
+:::::::::::::::::::::::
 
-Each entry contains a string describing a distutils project's distribution
-which this distribution renders obsolete, meaning that the two projects
-should not be installed at the same time.
+Indicates that this project is no longer being developed.  The named
+project provides a substitute or replacement.
 
-Version declarations can be supplied.  Version numbers must be in the
-format specified in `Version Specifiers`_.
+A version declaration may be supplied and must follow the rules described
+in `Version Specifiers`_.
 
-The most common use of this field will be in case a project name changes,
-e.g. Gorgon 2.3 gets renamed to Torqued Python 1.0.  When you install
-Torqued Python, the Gorgon distribution should be removed.
+The most common use of this field will be in case a project name changes.
 
 Examples::
 
-    Obsoletes-Dist: Gorgon
-    Obsoletes-Dist: OtherProject (<3.0)
+    Name: BadName
+    Obsoleted-By: AcceptableName
+    
+    Obsoleted-By: AcceptableName (>=4.0.0)
 
 
 Requires-Python (optional)
@@ -554,7 +552,6 @@ environment.
 Here are some example of fields using such markers::
 
    Requires-Dist: pywin32 (>1.0); sys.platform == 'win32'
-   Obsoletes-Dist: pywin31; sys.platform == 'win32'
    Requires-Dist: foo (1,!=1.3); platform.machine == 'i386'
    Requires-Dist: bar; python_version == '2.4' or python_version == '2.5'
    Requires-External: libxslt; 'linux' in sys.platform
@@ -590,7 +587,6 @@ The fields that benefit from this marker are:
 - Requires-Dist
 - Setup-Requires-Dist
 - Provides-Dist
-- Obsoletes-Dist
 - Classifier
 
 (The `extra` variable is only meaningful for Requires-Dist.)
@@ -608,6 +604,8 @@ Summary of Differences From PEP 345
 
 * Most fields are now optional.
 
+* Removed `Obsoletes-Dist`
+
 * Changed fields:
 
   - Description
@@ -619,6 +617,7 @@ Summary of Differences From PEP 345
   - Extension
   - Provides-Extra
   - Setup-Requires-Dist
+  - Obsoleted-By
 
 References
 ==========