Merged revisions 78446 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/branches/py3k

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  r78446 | eric.smith | 2010-02-25 09:58:13 -0500 (Thu, 25 Feb 2010) | 9 lines

  Merged revisions 78444 via svnmerge from
  svn+ssh://pythondev@svn.python.org/python/trunk

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    r78444 | eric.smith | 2010-02-25 09:26:33 -0500 (Thu, 25 Feb 2010) | 1 line

    Issue #7928: Document str.format element_index better.
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Doc/library/string.rst

@@ -199,7 +199,8 @@ The grammar for a replacement field is as follows:
       field_name: arg_name ("." `attribute_name` | "[" `element_index` "]")*
       arg_name: (`identifier` | `integer`)?
       attribute_name: `identifier`
-      element_index: `integer`
+      element_index: `integer` | `index_string`
+      index_string: <any source character except "]"> +
       conversion: "r" | "s" | "a"
       format_spec: <described in the next section>