Address GvR's comments.

pep-0393.txt

@@ -19,7 +19,8 @@ ordinal (1, 2, or 4 bytes). This will allow a space-efficient
 representation in common cases, but give access to full UCS-4 on all
 systems. For compatibility with existing APIs, several representations
 may exist in parallel; over time, this compatibility should be phased
-out.
+out. The distinction between narrow and wide Unicode builds is
+dropped.  An implementation of this PEP is available at [1]_.
 
 Rationale
 =========
@@ -206,10 +207,62 @@ should use the existing PyUnicode_AsUTF8String where possible
 converts a string to a char* (such as the ParseTuple functions) will
 use PyUnicode_AsUTF8 to compute a conversion.
 
+New API
+-------
+
+This section summarizes the API additions.
+
+Macros to access the internal representation of a Unicode object
+(read-only):
+
+- PyUnicode_IS_COMPACT_ASCII(o), PyUnicode_IS_COMPACT(o),
+  PyUnicode_IS_READY(o)
+- PyUnicode_GET_LENGTH(o)
+- PyUnicode_KIND(o), PyUnicode_CHARACTER_SIZE(o),
+  PyUnicode_MAX_CHAR_VALUE(o)
+- PyUnicode_DATA(o), PyUnicode_1BYTE_DATA(o), PyUnicode_2BYTE_DATA(o),
+  PyUnicode_4BYTE_DATA(o)
+
+Character access macros:
+
+- PyUnicode_READ(kind, data, index), PyUnicode_READ_CHAR(o, index)
+- PyUnicode_WRITE(kind, data, index, value)
+
+Other macros:
+
+- PyUnicode_READY(o)
+- PyUnicode_CONVERT_BYTES(from_type, tp_type, begin, end, to)
+
+String creation functions:
+
+- PyUnicode_New(size, maxchar)
+- PyUnicode_FromKindAndData(kind, data, size)
+- PyUnicode_Substring(o, start, end)
+- PyUnicode_Chr(ch)
+
+Character access utility functions:
+
+- PyUnicode_CopyCharacters(to, to_start, from, from_start, how_many)
+- PyUnicode_FindChar(str, ch, start, end, direction)
+
+Representation conversion:
+
+- PyUnicode_AsUCS4(o, buffer, buflen)
+- PyUnicode_AsUCS4Copy(o)
+- PyUnicode_AsUnicodeAndSize(o, size_out)
+- PyUnicode_AsUTF8(o)
+- PyUnicode_AsUTF8AndSize(o, size_out)
+
+UCS4 utility functions:
+
+- Py_UCS4_{strlen, strcpy, strcat, strncpy, strcmp, strncpy, strcmp,
+  strncmp, strchr, strrchr}
+
 Stable ABI
 ----------
 
-None of the functions in this PEP become part of the stable ABI.
+None of the functions in this PEP become part of the stable ABI
+(PEP 384).
 
 GDB Debugging Hooks
 -------------------
@@ -363,6 +416,12 @@ be necessary: PyUnicode_Find, PyUnicode_FindChar, PyUnicode_Ord, and
 PyUnicode_CopyCharacters help in analyzing and creating string
 objects, operating on indices instead of data pointers.
 
+References
+==========
+
+.. [1] PEP 393 branch
+       https://bitbucket.org/t0rsten/pep-393
+
 Copyright
 =========