Issue #24001: Argument Clinic converters now use accept={type}

instead of types={'type'} to specify the types the converter accepts.

Misc/NEWS

@@ -68,6 +68,9 @@ Documentation
 Tools/Demos
 -----------
 
+- Issue #24001: Argument Clinic converters now use accept={type}
+  instead of types={'type'} to specify the types the converter accepts.
+
 - Issue #23330: h2py now supports arbitrary filenames in #include.
 
 - Issue #24031: make patchcheck now supports git checkouts, too.

Modules/_dbmmodule.c

@@ -274,7 +274,7 @@ static PySequenceMethods dbm_as_sequence = {
 /*[clinic input]
 _dbm.dbm.get
 
-    key: str(types={'str', 'robuffer'}, length=True)
+    key: str(accept={str, robuffer}, length=True)
     default: object(c_default="NULL") = b''
     /
 
@@ -284,7 +284,7 @@ Return the value for key if present, otherwise default.
 static PyObject *
 _dbm_dbm_get_impl(dbmobject *self, const char *key,
                   Py_ssize_clean_t key_length, PyObject *default_value)
-/*[clinic end generated code: output=b44f95eba8203d93 input=fee97bbe85e84822]*/
+/*[clinic end generated code: output=b44f95eba8203d93 input=3c7c1afd9c508457]*/
 {
     datum dbm_key, val;
 
@@ -301,7 +301,7 @@ _dbm_dbm_get_impl(dbmobject *self, const char *key,
 
 /*[clinic input]
 _dbm.dbm.setdefault
-    key: str(types={'str', 'robuffer'}, length=True)
+    key: str(accept={str, robuffer}, length=True)
     default: object(c_default="NULL") = b''
     /
 
@@ -314,7 +314,7 @@ static PyObject *
 _dbm_dbm_setdefault_impl(dbmobject *self, const char *key,
                          Py_ssize_clean_t key_length,
                          PyObject *default_value)
-/*[clinic end generated code: output=52545886cf272161 input=6a3b99ae91f20203]*/
+/*[clinic end generated code: output=52545886cf272161 input=a66fcb7f18ee2f50]*/
 {
     datum dbm_key, val;
     Py_ssize_t tmp_size;

Modules/_elementtree.c

@@ -3206,14 +3206,14 @@ _elementtree.XMLParser.__init__
 
     html: object = NULL
     target: object = NULL
-    encoding: str(nullable=True) = NULL
+    encoding: str(accept={str, NoneType}) = NULL
 
 [clinic start generated code]*/
 
 static int
 _elementtree_XMLParser___init___impl(XMLParserObject *self, PyObject *html,
                                      PyObject *target, const char *encoding)
-/*[clinic end generated code: output=d6a16c63dda54441 input=a870da39c80d7d68]*/
+/*[clinic end generated code: output=d6a16c63dda54441 input=155bc5695baafffd]*/
 {
     self->entity = PyDict_New();
     if (!self->entity)

Modules/_gdbmmodule.c

@@ -383,7 +383,7 @@ _gdbm_gdbm_firstkey_impl(dbmobject *self)
 /*[clinic input]
 _gdbm.gdbm.nextkey
 
-    key: str(types={'str', 'robuffer'}, length=True)
+    key: str(accept={str, robuffer}, length=True)
     /
 
 Returns the key that follows key in the traversal.
@@ -400,7 +400,7 @@ to create a list in memory that contains them all:
 static PyObject *
 _gdbm_gdbm_nextkey_impl(dbmobject *self, const char *key,
                         Py_ssize_clean_t key_length)
-/*[clinic end generated code: output=192ab892de6eb2f6 input=df8e8828201214a6]*/
+/*[clinic end generated code: output=192ab892de6eb2f6 input=1eb2ff9b4b0e6ffd]*/
 {
     PyObject *v;
     datum dbm_key, nextkey;

Modules/_io/_iomodule.c

@@ -100,9 +100,9 @@ _io.open
     file: object
     mode: str = "r"
     buffering: int = -1
-    encoding: str(nullable=True) = NULL
-    errors: str(nullable=True) = NULL
-    newline: str(nullable=True) = NULL
+    encoding: str(accept={str, NoneType}) = NULL
+    errors: str(accept={str, NoneType}) = NULL
+    newline: str(accept={str, NoneType}) = NULL
     closefd: int(c_default="1") = True
     opener: object = None
 
@@ -230,7 +230,7 @@ static PyObject *
 _io_open_impl(PyModuleDef *module, PyObject *file, const char *mode,
               int buffering, const char *encoding, const char *errors,
               const char *newline, int closefd, PyObject *opener)
-/*[clinic end generated code: output=7615d0d746eb14d2 input=0541ce15691a82f2]*/
+/*[clinic end generated code: output=7615d0d746eb14d2 input=f4e1ca75223987bc]*/
 {
     unsigned i;
 

Modules/_io/bufferedio.c

@@ -101,26 +101,26 @@ _bufferediobase_readinto_generic(PyObject *self, Py_buffer *buffer, char readint
 
 /*[clinic input]
 _io._BufferedIOBase.readinto
-    buffer: Py_buffer(types={'rwbuffer'})
+    buffer: Py_buffer(accept={rwbuffer})
     /
 [clinic start generated code]*/
 
 static PyObject *
 _io__BufferedIOBase_readinto_impl(PyObject *self, Py_buffer *buffer)
-/*[clinic end generated code: output=8c8cda6684af8038 input=f8242a06c21763a0]*/
+/*[clinic end generated code: output=8c8cda6684af8038 input=00a6b9a38f29830a]*/
 {
     return _bufferediobase_readinto_generic(self, buffer, 0);
 }
 
 /*[clinic input]
 _io._BufferedIOBase.readinto1
-    buffer: Py_buffer(types={'rwbuffer'})
+    buffer: Py_buffer(accept={rwbuffer})
     /
 [clinic start generated code]*/
 
 static PyObject *
 _io__BufferedIOBase_readinto1_impl(PyObject *self, Py_buffer *buffer)
-/*[clinic end generated code: output=358623e4fd2b69d3 input=2003e706c730bd21]*/
+/*[clinic end generated code: output=358623e4fd2b69d3 input=ebad75b4aadfb9be]*/
 {
     return _bufferediobase_readinto_generic(self, buffer, 1);
 }
@@ -1065,26 +1065,26 @@ end:
 
 /*[clinic input]
 _io._Buffered.readinto
-    buffer: Py_buffer(types={'rwbuffer'})
+    buffer: Py_buffer(accept={rwbuffer})
     /
 [clinic start generated code]*/
 
 static PyObject *
 _io__Buffered_readinto_impl(buffered *self, Py_buffer *buffer)
-/*[clinic end generated code: output=bcb376580b1d8170 input=962b7496eac38b3a]*/
+/*[clinic end generated code: output=bcb376580b1d8170 input=ed6b98b7a20a3008]*/
 {
     return _buffered_readinto_generic(self, buffer, 0);
 }
 
 /*[clinic input]
 _io._Buffered.readinto1
-    buffer: Py_buffer(types={'rwbuffer'})
+    buffer: Py_buffer(accept={rwbuffer})
     /
 [clinic start generated code]*/
 
 static PyObject *
 _io__Buffered_readinto1_impl(buffered *self, Py_buffer *buffer)
-/*[clinic end generated code: output=6e5c6ac5868205d6 input=834614d93f0adeb5]*/
+/*[clinic end generated code: output=6e5c6ac5868205d6 input=4455c5d55fdf1687]*/
 {
     return _buffered_readinto_generic(self, buffer, 1);
 }

Modules/_io/bytesio.c

@@ -541,7 +541,7 @@ _io_BytesIO_readlines_impl(bytesio *self, PyObject *arg)
 
 /*[clinic input]
 _io.BytesIO.readinto
-    buffer: Py_buffer(types={'rwbuffer'})
+    buffer: Py_buffer(accept={rwbuffer})
     /
 
 Read up to len(buffer) bytes into buffer.
@@ -552,7 +552,7 @@ is set not to block as has no data to read.
 
 static PyObject *
 _io_BytesIO_readinto_impl(bytesio *self, Py_buffer *buffer)
-/*[clinic end generated code: output=a5d407217dcf0639 input=d289da851c7c4159]*/
+/*[clinic end generated code: output=a5d407217dcf0639 input=71581f32635c3a31]*/
 {
     Py_ssize_t len, n;
 

Modules/_io/fileio.c

@@ -603,7 +603,7 @@ _io_FileIO_seekable_impl(fileio *self)
 
 /*[clinic input]
 _io.FileIO.readinto
-    buffer: Py_buffer(types={'rwbuffer'})
+    buffer: Py_buffer(accept={rwbuffer})
     /
 
 Same as RawIOBase.readinto().
@@ -611,7 +611,7 @@ Same as RawIOBase.readinto().
 
 static PyObject *
 _io_FileIO_readinto_impl(fileio *self, Py_buffer *buffer)
-/*[clinic end generated code: output=b01a5a22c8415cb4 input=5edd8327498d468c]*/
+/*[clinic end generated code: output=b01a5a22c8415cb4 input=4721d7b68b154eaf]*/
 {
     Py_ssize_t n;
     int err;

Modules/_io/textio.c

@@ -789,9 +789,9 @@ static encodefuncentry encodefuncs[] = {
 /*[clinic input]
 _io.TextIOWrapper.__init__
     buffer: object
-    encoding: str(nullable=True) = NULL
-    errors: str(nullable=True) = NULL
-    newline: str(nullable=True) = NULL
+    encoding: str(accept={str, NoneType}) = NULL
+    errors: str(accept={str, NoneType}) = NULL
+    newline: str(accept={str, NoneType}) = NULL
     line_buffering: int(c_default="0") = False
     write_through: int(c_default="0") = False
 
@@ -830,7 +830,7 @@ _io_TextIOWrapper___init___impl(textio *self, PyObject *buffer,
                                 const char *encoding, const char *errors,
                                 const char *newline, int line_buffering,
                                 int write_through)
-/*[clinic end generated code: output=56a83402ce2a8381 input=1f20decb8d54a4ec]*/
+/*[clinic end generated code: output=56a83402ce2a8381 input=3126cb3101a2c99b]*/
 {
     PyObject *raw, *codec_info = NULL;
     _PyIO_State *state = NULL;

Modules/_ssl.c

@@ -1877,7 +1877,7 @@ _ssl__SSLSocket_pending_impl(PySSLSocket *self)
 _ssl._SSLSocket.read
     size as len: int
     [
-    buffer: Py_buffer(types={'rwbuffer'})
+    buffer: Py_buffer(accept={rwbuffer})
     ]
     /
 
@@ -1887,7 +1887,7 @@ Read up to size bytes from the SSL socket.
 static PyObject *
 _ssl__SSLSocket_read_impl(PySSLSocket *self, int len, int group_right_1,
                           Py_buffer *buffer)
-/*[clinic end generated code: output=00097776cec2a0af input=4a0bbd2859e817b0]*/
+/*[clinic end generated code: output=00097776cec2a0af input=ff157eb918d0905b]*/
 {
     PyObject *dest = NULL;
     char *mem;
@@ -3799,7 +3799,7 @@ static PyTypeObject PySSLMemoryBIO_Type = {
 /* helper routines for seeding the SSL PRNG */
 /*[clinic input]
 _ssl.RAND_add
-    string as view: Py_buffer(types={'str', 'buffer'})
+    string as view: Py_buffer(accept={str, buffer})
     entropy: double
     /
 
@@ -3811,7 +3811,7 @@ string.  See RFC 1750.
 
 static PyObject *
 _ssl_RAND_add_impl(PyModuleDef *module, Py_buffer *view, double entropy)
-/*[clinic end generated code: output=0f8d5c8cce328958 input=c98b11d606b354bc]*/
+/*[clinic end generated code: output=0f8d5c8cce328958 input=580c85e6a3a4fe29]*/
 {
     const char *buf;
     Py_ssize_t len, written;

Modules/_tkinter.c

@@ -3101,7 +3101,7 @@ _tkinter__flatten(PyModuleDef *module, PyObject *item)
 /*[clinic input]
 _tkinter.create
 
-    screenName: str(nullable=True) = NULL
+    screenName: str(accept={str, NoneType}) = NULL
     baseName: str = NULL
     className: str = "Tk"
     interactive: int(c_default="0") = False
@@ -3110,7 +3110,7 @@ _tkinter.create
         if false, then Tk_Init() doesn't get called
     sync: int(c_default="0") = False
         if true, then pass -sync to wish
-    use: str(nullable=True) = NULL
+    use: str(accept={str, NoneType}) = NULL
         if not None, then pass -use to wish
     /
 
@@ -3121,7 +3121,7 @@ _tkinter_create_impl(PyModuleDef *module, const char *screenName,
                      const char *baseName, const char *className,
                      int interactive, int wantobjects, int wantTk, int sync,
                      const char *use)
-/*[clinic end generated code: output=b8847800fc3b27eb input=c133c59a99dd0086]*/
+/*[clinic end generated code: output=b8847800fc3b27eb input=0d522aad1cb0ca0e]*/
 {
     /* XXX baseName is not used anymore;
      * try getting rid of it. */

Modules/arraymodule.c

@@ -1600,7 +1600,7 @@ frombytes(arrayobject *self, Py_buffer *buffer)
 /*[clinic input]
 array.array.fromstring
 
-    buffer: Py_buffer(types={'str', 'buffer'})
+    buffer: Py_buffer(accept={str, buffer})
     /
 
 Appends items from the string, interpreting it as an array of machine values, as if it had been read from a file using the fromfile() method).
@@ -1610,7 +1610,7 @@ This method is deprecated. Use frombytes instead.
 
 static PyObject *
 array_array_fromstring_impl(arrayobject *self, Py_buffer *buffer)
-/*[clinic end generated code: output=31c4baa779df84ce input=fdde1a56cbe2b05b]*/
+/*[clinic end generated code: output=31c4baa779df84ce input=a3341a512e11d773]*/
 {
     if (PyErr_WarnEx(PyExc_DeprecationWarning,
             "fromstring() is deprecated. Use frombytes() instead.", 2) != 0)
@@ -1929,7 +1929,7 @@ make_array(PyTypeObject *arraytype, char typecode, PyObject *items)
 array._array_reconstructor
 
     arraytype: object(type="PyTypeObject *")
-    typecode: int(types={'str'})
+    typecode: int(accept={str})
     mformat_code: int(type="enum machine_format_code")
     items: object
     /
@@ -1942,7 +1942,7 @@ array__array_reconstructor_impl(PyModuleDef *module, PyTypeObject *arraytype,
                                 int typecode,
                                 enum machine_format_code mformat_code,
                                 PyObject *items)
-/*[clinic end generated code: output=6ecbf0e8e4d92ab9 input=a9ae223306d7b262]*/
+/*[clinic end generated code: output=6ecbf0e8e4d92ab9 input=2464dc8f4c7736b5]*/
 {
     PyObject *converted_items;
     PyObject *result;

Modules/cjkcodecs/multibytecodec.c

@@ -544,7 +544,7 @@ errorexit:
 _multibytecodec.MultibyteCodec.encode
 
   input: object
-  errors: str(nullable=True) = NULL
+  errors: str(accept={str, NoneType}) = NULL
 
 Return an encoded string version of `input'.
 
@@ -558,7 +558,7 @@ static PyObject *
 _multibytecodec_MultibyteCodec_encode_impl(MultibyteCodecObject *self,
                                            PyObject *input,
                                            const char *errors)
-/*[clinic end generated code: output=7b26652045ba56a9 input=252e7ee695867b2d]*/
+/*[clinic end generated code: output=7b26652045ba56a9 input=05f6ced3c8dd0582]*/
 {
     MultibyteCodec_State state;
     PyObject *errorcb, *r, *ucvt;
@@ -613,7 +613,7 @@ errorexit:
 _multibytecodec.MultibyteCodec.decode
 
   input: Py_buffer
-  errors: str(nullable=True) = NULL
+  errors: str(accept={str, NoneType}) = NULL
 
 Decodes 'input'.
 
@@ -627,7 +627,7 @@ static PyObject *
 _multibytecodec_MultibyteCodec_decode_impl(MultibyteCodecObject *self,
                                            Py_buffer *input,
                                            const char *errors)
-/*[clinic end generated code: output=ff419f65bad6cc77 input=37e1d9236e3ce8f3]*/
+/*[clinic end generated code: output=ff419f65bad6cc77 input=a7d45f87f75e5e02]*/
 {
     MultibyteCodec_State state;
     MultibyteDecodeBuffer buf;

Modules/pyexpat.c

@@ -911,7 +911,7 @@ pyexpat_xmlparser_GetInputContext_impl(xmlparseobject *self)
 /*[clinic input]
 pyexpat.xmlparser.ExternalEntityParserCreate
 
-    context: str(nullable=True)
+    context: str(accept={str, NoneType})
     encoding: str = NULL
     /
 
@@ -922,7 +922,7 @@ static PyObject *
 pyexpat_xmlparser_ExternalEntityParserCreate_impl(xmlparseobject *self,
                                                   const char *context,
                                                   const char *encoding)
-/*[clinic end generated code: output=535cda9d7a0fbcd6 input=283206575d960272]*/
+/*[clinic end generated code: output=535cda9d7a0fbcd6 input=b906714cc122c322]*/
 {
     xmlparseobject *new_parser;
     int i;
@@ -1546,8 +1546,8 @@ static PyTypeObject Xmlparsetype = {
 /*[clinic input]
 pyexpat.ParserCreate
 
-    encoding: str(nullable=True) = NULL
-    namespace_separator: str(nullable=True) = NULL
+    encoding: str(accept={str, NoneType}) = NULL
+    namespace_separator: str(accept={str, NoneType}) = NULL
     intern: object = NULL
 
 Return a new XML parser object.
@@ -1556,7 +1556,7 @@ Return a new XML parser object.
 static PyObject *
 pyexpat_ParserCreate_impl(PyModuleDef *module, const char *encoding,
                           const char *namespace_separator, PyObject *intern)
-/*[clinic end generated code: output=81fccd233e1743a8 input=71b9f471aa6f8f86]*/
+/*[clinic end generated code: output=81fccd233e1743a8 input=23d29704acad385d]*/
 {
     PyObject *result;
     int intern_decref = 0;

Modules/unicodedata.c

@@ -107,7 +107,7 @@ new_previous_version(const char*name, const change_record* (*getrecord)(Py_UCS4)
 unicodedata.UCD.decimal
 
     self: self
-    chr: int(types={'str'})
+    chr: int(accept={str})
     default: object=NULL
     /
 
@@ -121,7 +121,7 @@ ValueError is raised.
 static PyObject *
 unicodedata_UCD_decimal_impl(PyObject *self, int chr,
                              PyObject *default_value)
-/*[clinic end generated code: output=be23376e1a185231 input=3acf7f2238874a49]*/
+/*[clinic end generated code: output=be23376e1a185231 input=933f8107993f23d0]*/
 {
     int have_old = 0;
     long rc;
@@ -160,7 +160,7 @@ unicodedata_UCD_decimal_impl(PyObject *self, int chr,
 unicodedata.UCD.digit
 
     self: self
-    chr: int(types={'str'})
+    chr: int(accept={str})
     default: object=NULL
     /
 
@@ -173,7 +173,7 @@ ValueError is raised.
 
 static PyObject *
 unicodedata_UCD_digit_impl(PyObject *self, int chr, PyObject *default_value)
-/*[clinic end generated code: output=96e18c950171fd2f input=733f093b399f5ab6]*/
+/*[clinic end generated code: output=96e18c950171fd2f input=e27d6e4565cd29f2]*/
 {
     long rc;
     Py_UCS4 c = (Py_UCS4)chr;
@@ -195,7 +195,7 @@ unicodedata_UCD_digit_impl(PyObject *self, int chr, PyObject *default_value)
 unicodedata.UCD.numeric
 
     self: self
-    chr: int(types={'str'})
+    chr: int(accept={str})
     default: object=NULL
     /
 
@@ -209,7 +209,7 @@ ValueError is raised.
 static PyObject *
 unicodedata_UCD_numeric_impl(PyObject *self, int chr,
                              PyObject *default_value)
-/*[clinic end generated code: output=53ce281fe85b10c4 input=c5875fa7cc768fb2]*/
+/*[clinic end generated code: output=53ce281fe85b10c4 input=fdf5871a5542893c]*/
 {
     int have_old = 0;
     double rc;
@@ -247,7 +247,7 @@ unicodedata_UCD_numeric_impl(PyObject *self, int chr,
 unicodedata.UCD.category
 
     self: self
-    chr: int(types={'str'})
+    chr: int(accept={str})
     /
 
 Returns the general category assigned to the character chr as string.
@@ -255,7 +255,7 @@ Returns the general category assigned to the character chr as string.
 
 static PyObject *
 unicodedata_UCD_category_impl(PyObject *self, int chr)
-/*[clinic end generated code: output=8571539ee2e6783a input=f5edd6fd04bd455d]*/
+/*[clinic end generated code: output=8571539ee2e6783a input=27d6f3d85050bc06]*/
 {
     int index;
     Py_UCS4 c = (Py_UCS4)chr;
@@ -272,7 +272,7 @@ unicodedata_UCD_category_impl(PyObject *self, int chr)
 unicodedata.UCD.bidirectional
 
     self: self
-    chr: int(types={'str'})
+    chr: int(accept={str})
     /
 
 Returns the bidirectional class assigned to the character chr as string.
@@ -282,7 +282,7 @@ If no such value is defined, an empty string is returned.
 
 static PyObject *
 unicodedata_UCD_bidirectional_impl(PyObject *self, int chr)
-/*[clinic end generated code: output=d36310ce2039bb92 input=5ce2f877b35305b5]*/
+/*[clinic end generated code: output=d36310ce2039bb92 input=b3d8f42cebfcf475]*/
 {
     int index;
     Py_UCS4 c = (Py_UCS4)chr;
@@ -301,7 +301,7 @@ unicodedata_UCD_bidirectional_impl(PyObject *self, int chr)
 unicodedata.UCD.combining -> int
 
     self: self
-    chr: int(types={'str'})
+    chr: int(accept={str})
     /
 
 Returns the canonical combining class assigned to the character chr as integer.
@@ -311,7 +311,7 @@ Returns 0 if no combining class is defined.
 
 static int
 unicodedata_UCD_combining_impl(PyObject *self, int chr)
-/*[clinic end generated code: output=cad056d0cb6a5920 input=9125ea7d50b319e7]*/
+/*[clinic end generated code: output=cad056d0cb6a5920 input=9f2d6b2a95d0a22a]*/
 {
     int index;
     Py_UCS4 c = (Py_UCS4)chr;
@@ -328,7 +328,7 @@ unicodedata_UCD_combining_impl(PyObject *self, int chr)
 unicodedata.UCD.mirrored -> int
 
     self: self
-    chr: int(types={'str'})
+    chr: int(accept={str})
     /
 
 Returns the mirrored property assigned to the character chr as integer.
@@ -339,7 +339,7 @@ character in bidirectional text, 0 otherwise.
 
 static int
 unicodedata_UCD_mirrored_impl(PyObject *self, int chr)
-/*[clinic end generated code: output=2532dbf8121b50e6 input=4e51e8aaf8d7e23e]*/
+/*[clinic end generated code: output=2532dbf8121b50e6 input=5dd400d351ae6f3b]*/
 {
     int index;
     Py_UCS4 c = (Py_UCS4)chr;
@@ -358,7 +358,7 @@ unicodedata_UCD_mirrored_impl(PyObject *self, int chr)
 unicodedata.UCD.east_asian_width
 
     self: self
-    chr: int(types={'str'})
+    chr: int(accept={str})
     /
 
 Returns the east asian width assigned to the character chr as string.
@@ -366,7 +366,7 @@ Returns the east asian width assigned to the character chr as string.
 
 static PyObject *
 unicodedata_UCD_east_asian_width_impl(PyObject *self, int chr)
-/*[clinic end generated code: output=484e8537d9ee8197 input=f93c61f37276c8f0]*/
+/*[clinic end generated code: output=484e8537d9ee8197 input=c4854798aab026e0]*/
 {
     int index;
     Py_UCS4 c = (Py_UCS4)chr;
@@ -383,7 +383,7 @@ unicodedata_UCD_east_asian_width_impl(PyObject *self, int chr)
 unicodedata.UCD.decomposition
 
     self: self
-    chr: int(types={'str'})
+    chr: int(accept={str})
     /
 
 Returns the character decomposition mapping assigned to the character chr as string.
@@ -393,7 +393,7 @@ An empty string is returned in case no such mapping is defined.
 
 static PyObject *
 unicodedata_UCD_decomposition_impl(PyObject *self, int chr)
-/*[clinic end generated code: output=7d699f3ec7565d27 input=7f2c0ee66d75468f]*/
+/*[clinic end generated code: output=7d699f3ec7565d27 input=e4c12459ad68507b]*/
 {
     char decomp[256];
     int code, index, count;
@@ -1180,7 +1180,7 @@ static const _PyUnicode_Name_CAPI hashAPI =
 unicodedata.UCD.name
 
     self: self
-    chr: int(types={'str'})
+    chr: int(accept={str})
     default: object=NULL
     /
 
@@ -1192,7 +1192,7 @@ ValueError is raised.
 
 static PyObject *
 unicodedata_UCD_name_impl(PyObject *self, int chr, PyObject *default_value)
-/*[clinic end generated code: output=6bbb37a326407707 input=51ee2f971c918113]*/
+/*[clinic end generated code: output=6bbb37a326407707 input=3e0367f534de56d9]*/
 {
     char name[NAME_MAXLEN];
     Py_UCS4 c = (Py_UCS4)chr;
@@ -1215,7 +1215,7 @@ unicodedata_UCD_name_impl(PyObject *self, int chr, PyObject *default_value)
 unicodedata.UCD.lookup
 
     self: self
-    name: str(types={'str', 'robuffer'}, length=True)
+    name: str(accept={str, robuffer}, length=True)
     /
 
 Look up character by name.
@@ -1227,7 +1227,7 @@ corresponding character.  If not found, KeyError is raised.
 static PyObject *
 unicodedata_UCD_lookup_impl(PyObject *self, const char *name,
                             Py_ssize_clean_t name_length)
-/*[clinic end generated code: output=765cb8186788e6be input=f2bf29706135a590]*/
+/*[clinic end generated code: output=765cb8186788e6be input=2dfe682c2491447a]*/
 {
     Py_UCS4 code;
     unsigned int index;

Tools/clinic/clinic.py

@@ -26,8 +26,12 @@ import sys
 import tempfile
 import textwrap
 import traceback
+import types
 import uuid
 
+from types import *
+NoneType = type(None)
+
 # TODO:
 #
 # soon:
@@ -2526,18 +2530,18 @@ class unsigned_short_converter(CConverter):
         if not bitwise:
             fail("Unsigned shorts must be bitwise (for now).")
 
-@add_legacy_c_converter('C', types={'str'})
+@add_legacy_c_converter('C', accept={str})
 class int_converter(CConverter):
     type = 'int'
     default_type = int
     format_unit = 'i'
     c_ignored_default = "0"
 
-    def converter_init(self, *, types={'int'}, type=None):
-        if types == {'str'}:
+    def converter_init(self, *, accept={int}, type=None):
+        if accept == {str}:
             self.format_unit = 'C'
-        elif types != {'int'}:
-            fail("int_converter: illegal 'types' argument " + repr(types))
+        elif accept != {int}:
+            fail("int_converter: illegal 'accept' argument " + repr(accept))
         if type != None:
             self.type = type
 
@@ -2629,17 +2633,22 @@ class object_converter(CConverter):
 
 
 #
-# We define three string conventions for buffer types in the 'types' argument:
-#  'buffer' : any object supporting the buffer interface
-#  'rwbuffer': any object supporting the buffer interface, but must be writeable
-#  'robuffer': any object supporting the buffer interface, but must not be writeable
+# We define three conventions for buffer types in the 'accept' argument:
+#
+#  buffer  : any object supporting the buffer interface
+#  rwbuffer: any object supporting the buffer interface, but must be writeable
+#  robuffer: any object supporting the buffer interface, but must not be writeable
 #
 
-@add_legacy_c_converter('s#', types={"str", "robuffer"}, length=True)
-@add_legacy_c_converter('y', types={"robuffer"})
-@add_legacy_c_converter('y#', types={"robuffer"}, length=True)
-@add_legacy_c_converter('z', nullable=True)
-@add_legacy_c_converter('z#', types={"str", "robuffer"}, nullable=True, length=True)
+class buffer: pass
+class rwbuffer: pass
+class robuffer: pass
+
+@add_legacy_c_converter('s#', accept={str, robuffer}, length=True)
+@add_legacy_c_converter('y', accept={robuffer})
+@add_legacy_c_converter('y#', accept={robuffer}, length=True)
+@add_legacy_c_converter('z', accept={str, NoneType})
+@add_legacy_c_converter('z#', accept={str, NoneType}, length=True)
 # add_legacy_c_converter not supported for es, es#, et, et#
 # because of their extra encoding argument
 class str_converter(CConverter):
@@ -2647,45 +2656,47 @@ class str_converter(CConverter):
     default_type = (str, Null, NoneType)
     format_unit = 's'
 
-    def converter_init(self, *, encoding=None, types={"str"},
-        length=False, nullable=False, zeroes=False):
+    def converter_init(self, *, encoding=None, accept={str}, length=False, zeroes=False):
 
         self.length = bool(length)
 
-        is_b_or_ba = types == {"bytes", "bytearray"}
-        is_str = types == {"str"}
-        is_robuffer = types == {"robuffer"}
-        is_str_or_robuffer = types == {"str", "robuffer"}
+        is_b_or_ba = accept == {bytes, bytearray}
+        is_b_or_ba_or_none = accept == {bytes, bytearray, NoneType}
+        is_str = accept == {str}
+        is_str_or_none = accept == {str, NoneType}
+        is_robuffer = accept == {robuffer}
+        is_str_or_robuffer = accept == {str, robuffer}
+        is_str_or_robuffer_or_none = accept == {str, robuffer, NoneType}
 
         format_unit = None
 
         if encoding:
             self.encoding = encoding
 
-            if   is_str     and not length and not zeroes and not nullable:
+            if   is_str             and not length and not zeroes:
                 format_unit = 'es'
-            elif is_str     and     length and     zeroes and     nullable:
+            elif is_str_or_none     and     length and     zeroes:
                 format_unit = 'es#'
-            elif is_b_or_ba and not length and not zeroes and not nullable:
+            elif is_b_or_ba         and not length and not zeroes:
                 format_unit = 'et'
-            elif is_b_or_ba and     length and     zeroes and     nullable:
+            elif is_b_or_ba_or_none and     length and     zeroes:
                 format_unit = 'et#'
 
         else:
             if zeroes:
                 fail("str_converter: illegal combination of arguments (zeroes is only legal with an encoding)")
 
-            if is_str               and not length and not nullable:
+            if is_str               and not length:
                 format_unit = 's'
-            elif is_str             and not length and     nullable:
+            elif is_str_or_none     and not length:
                 format_unit = 'z'
-            elif is_robuffer        and not length and not nullable:
+            elif is_robuffer        and not length:
                 format_unit = 'y'
-            elif is_robuffer        and     length and not nullable:
+            elif is_robuffer        and     length:
                 format_unit = 'y#'
-            elif is_str_or_robuffer and     length and not nullable:
+            elif is_str_or_robuffer and     length:
                 format_unit = 's#'
-            elif is_str_or_robuffer and     length and     nullable:
+            elif is_str_or_robuffer_or_none and     length:
                 format_unit = 'z#'
 
         if not format_unit:
@@ -2696,12 +2707,12 @@ class str_converter(CConverter):
 class PyBytesObject_converter(CConverter):
     type = 'PyBytesObject *'
     format_unit = 'S'
-    # types = {'bytes'}
+    # accept = {bytes}
 
 class PyByteArrayObject_converter(CConverter):
     type = 'PyByteArrayObject *'
     format_unit = 'Y'
-    # types = {'bytearray'}
+    # accept = {bytearray}
 
 class unicode_converter(CConverter):
     type = 'PyObject *'
@@ -2709,45 +2720,44 @@ class unicode_converter(CConverter):
     format_unit = 'U'
 
 @add_legacy_c_converter('u#', length=True)
-@add_legacy_c_converter('Z', nullable=True)
-@add_legacy_c_converter('Z#', nullable=True, length=True)
+@add_legacy_c_converter('Z', accept={str, NoneType})
+@add_legacy_c_converter('Z#', accept={str, NoneType}, length=True)
 class Py_UNICODE_converter(CConverter):
     type = 'Py_UNICODE *'
     default_type = (str, Null, NoneType)
     format_unit = 'u'
 
-    def converter_init(self, *, nullable=False, length=False):
-        format_unit = 'Z' if nullable else 'u'
+    def converter_init(self, *, accept={str}, length=False):
+        format_unit = 'Z' if accept=={str, NoneType} else 'u'
         if length:
             format_unit += '#'
             self.length = True
         self.format_unit = format_unit
 
-@add_legacy_c_converter('s*', types={'str', 'buffer'})
-@add_legacy_c_converter('z*', types={'str', 'buffer'}, nullable=True)
-@add_legacy_c_converter('w*', types={'rwbuffer'})
+@add_legacy_c_converter('s*', accept={str, buffer})
+@add_legacy_c_converter('z*', accept={str, buffer, NoneType})
+@add_legacy_c_converter('w*', accept={rwbuffer})
 class Py_buffer_converter(CConverter):
     type = 'Py_buffer'
     format_unit = 'y*'
     impl_by_reference = True
     c_ignored_default = "{NULL, NULL}"
 
-    def converter_init(self, *, types={'buffer'}, nullable=False):
+    def converter_init(self, *, accept={buffer}):
         if self.default not in (unspecified, None):
             fail("The only legal default value for Py_buffer is None.")
+
         self.c_default = self.c_ignored_default
 
-        format_unit = None
-        if types == {'str', 'buffer'}:
-            format_unit = 's*' if not nullable else 'z*'
-        else:
-            if nullable:
-                fail('Py_buffer_converter: illegal combination of arguments (nullable=True)')
-            elif types == {'buffer'}:
+        if accept == {str, buffer, NoneType}:
+            format_unit = 'z*'
+        elif accept == {str, buffer}:
+            format_unit = 's*'
+        elif accept == {buffer}:
             format_unit = 'y*'
-            elif types == {'rwbuffer'}:
+        elif accept == {rwbuffer}:
             format_unit = 'w*'
-        if not format_unit:
+        else:
             fail("Py_buffer_converter: illegal combination of arguments")
 
         self.format_unit = format_unit
@@ -3030,6 +3040,24 @@ class DecodeFSDefault_return_converter(CReturnConverter):
             'return_value = PyUnicode_DecodeFSDefault(_return_value);\n')
 
 
+def eval_ast_expr(node, globals, *, filename='-'):
+    """
+    Takes an ast.Expr node.  Compiles and evaluates it.
+    Returns the result of the expression.
+
+    globals represents the globals dict the expression
+    should see.  (There's no equivalent for "locals" here.)
+    """
+
+    if isinstance(node, ast.Expr):
+        node = node.value
+
+    node = ast.Expression(node)
+    co = compile(node, filename, 'eval')
+    fn = types.FunctionType(co, globals)
+    return fn()
+
+
 class IndentStack:
     def __init__(self):
         self.indents = []
@@ -3617,7 +3645,7 @@ class DSLParser:
         except SyntaxError:
             try:
                 # the last = was probably inside a function call, like
-                #   i: int(nullable=True)
+                #   c: int(accept={str})
                 # so assume there was no actual default value.
                 default = None
                 ast_input = "def x({}): pass".format(line)
@@ -3628,6 +3656,14 @@ class DSLParser:
             fail("Function " + self.function.name + " has an invalid parameter declaration:\n\t" + line)
 
         function_args = module.body[0].args
+
+        if len(function_args.args) > 1:
+            fail("Function " + self.function.name + " has an invalid parameter declaration (comma?):\n\t" + line)
+        if function_args.defaults or function_args.kw_defaults:
+            fail("Function " + self.function.name + " has an invalid parameter declaration (default value?):\n\t" + line)
+        if function_args.vararg or function_args.kwarg:
+            fail("Function " + self.function.name + " has an invalid parameter declaration (*args? **kwargs?):\n\t" + line)
+
         parameter = function_args.args[0]
 
         parameter_name = parameter.arg
@@ -3790,7 +3826,9 @@ class DSLParser:
             fail("Annotations must be either a name, a function call, or a string.")
 
         name = annotation.func.id
-        kwargs = {node.arg: ast.literal_eval(node.value) for node in annotation.keywords}
+        symbols = globals()
+
+        kwargs = {node.arg: eval_ast_expr(node.value, symbols) for node in annotation.keywords}
         return name, False, kwargs
 
     def parse_special_symbol(self, symbol):