PEP 622: Strengthen the argument for _ as wildcard (#1488)

See https://github.com/gvanrossum/patma/issues/93#issuecomment-650723402

Co-authored-by: Brandt Bucher <brandtbucher@gmail.com>

pep-0622.rst

@@ -981,7 +981,6 @@ A small collection of example code is
 `available on GitHub <https://github.com/gvanrossum/patma/tree/master/examples>`_.
 
 
-
 .. _rejected ideas:
 
 Rejected Ideas
@@ -1384,12 +1383,29 @@ the other uses of ``...`` in Python, but that water is already under
 the bridge.)
 
 Another proposal was to use ``?``.  This could be acceptable, although
-it would require modifying the tokenizer.  But ``_`` is already used
+it would require modifying the tokenizer.
+
+Also, ``_`` is already used
 as a throwaway target in other contexts, and this use is pretty
 similar.  This example is from ``difflib.py`` in the stdlib::
 
   for tag, _, _, j1, j2 in group: ...
 
+Perhaps the most convincing argument is that ``_`` is used as the
+wildcard in every other language we've looked at supporting pattern
+matching: C#, Elixir, Erlang, F#, Haskell, Mathematica, OCaml, Ruby,
+Rust, Scala, and Swift.  Now, in general, we should not be concerned
+too much with what another language does, since Python is clearly
+different from all these languages.  However, if there is such an
+overwhelming and strong consensus, Python should not go out of its way
+to do something completely different -- particularly given that ``_``
+works well in Python and is already in use as a throwaway target.
+
+Note that ``_`` is not assigned to by patterns -- this avoids
+conflicts with the use of ``_`` as a marker for translatable strings
+and an alias for ``gettext.gettext``, as recommended by the
+``gettext`` module documentation.
+
 Use some other syntax instead of ``|`` for OR patterns
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