From 442f20996dcd994d1024e5cad7f66a4595352eb2 Mon Sep 17 00:00:00 2001 From: Benjamin Peterson Date: Thu, 6 Dec 2012 17:41:04 -0500 Subject: [PATCH] create NameConstant AST class for None, True, and False literals (closes #16619) --- Include/Python-ast.h | 12 +++++-- Include/asdl.h | 1 + Lib/ast.py | 6 ++-- Lib/test/test_ast.py | 13 +++++--- Lib/test/test_syntax.py | 4 +-- Misc/NEWS | 4 +++ Parser/Python.asdl | 4 +-- Parser/asdl.py | 2 +- Parser/asdl_c.py | 12 +++++++ Python/Python-ast.c | 73 +++++++++++++++++++++++++++++++++++++++++ Python/ast.c | 22 ++++++++++--- Python/compile.c | 21 ++++++++---- Python/peephole.c | 46 -------------------------- Python/symtable.c | 1 + Tools/parser/unparse.py | 3 ++ 15 files changed, 152 insertions(+), 72 deletions(-) diff --git a/Include/Python-ast.h b/Include/Python-ast.h index 7ad6cb370b7..9d88d5d616a 100644 --- a/Include/Python-ast.h +++ b/Include/Python-ast.h @@ -182,8 +182,9 @@ enum _expr_kind {BoolOp_kind=1, BinOp_kind=2, UnaryOp_kind=3, Lambda_kind=4, SetComp_kind=9, DictComp_kind=10, GeneratorExp_kind=11, Yield_kind=12, YieldFrom_kind=13, Compare_kind=14, Call_kind=15, Num_kind=16, Str_kind=17, Bytes_kind=18, - Ellipsis_kind=19, Attribute_kind=20, Subscript_kind=21, - Starred_kind=22, Name_kind=23, List_kind=24, Tuple_kind=25}; + NameConstant_kind=19, Ellipsis_kind=20, Attribute_kind=21, + Subscript_kind=22, Starred_kind=23, Name_kind=24, + List_kind=25, Tuple_kind=26}; struct _expr { enum _expr_kind kind; union { @@ -278,6 +279,10 @@ struct _expr { bytes s; } Bytes; + struct { + singleton value; + } NameConstant; + struct { expr_ty value; identifier attr; @@ -509,6 +514,9 @@ expr_ty _Py_Num(object n, int lineno, int col_offset, PyArena *arena); expr_ty _Py_Str(string s, int lineno, int col_offset, PyArena *arena); #define Bytes(a0, a1, a2, a3) _Py_Bytes(a0, a1, a2, a3) expr_ty _Py_Bytes(bytes s, int lineno, int col_offset, PyArena *arena); +#define NameConstant(a0, a1, a2, a3) _Py_NameConstant(a0, a1, a2, a3) +expr_ty _Py_NameConstant(singleton value, int lineno, int col_offset, PyArena + *arena); #define Ellipsis(a0, a1, a2) _Py_Ellipsis(a0, a1, a2) expr_ty _Py_Ellipsis(int lineno, int col_offset, PyArena *arena); #define Attribute(a0, a1, a2, a3, a4, a5) _Py_Attribute(a0, a1, a2, a3, a4, a5) diff --git a/Include/asdl.h b/Include/asdl.h index 6bf618f3e96..0789ad870be 100644 --- a/Include/asdl.h +++ b/Include/asdl.h @@ -5,6 +5,7 @@ typedef PyObject * identifier; typedef PyObject * string; typedef PyObject * bytes; typedef PyObject * object; +typedef PyObject * singleton; /* It would be nice if the code generated by asdl_c.py was completely independent of Python, but it is a goal the requires too much work diff --git a/Lib/ast.py b/Lib/ast.py index 13f59f9dfa2..02c3b2867fa 100644 --- a/Lib/ast.py +++ b/Lib/ast.py @@ -42,7 +42,6 @@ def literal_eval(node_or_string): Python literal structures: strings, bytes, numbers, tuples, lists, dicts, sets, booleans, and None. """ - _safe_names = {'None': None, 'True': True, 'False': False} if isinstance(node_or_string, str): node_or_string = parse(node_or_string, mode='eval') if isinstance(node_or_string, Expression): @@ -61,9 +60,8 @@ def literal_eval(node_or_string): elif isinstance(node, Dict): return dict((_convert(k), _convert(v)) for k, v in zip(node.keys, node.values)) - elif isinstance(node, Name): - if node.id in _safe_names: - return _safe_names[node.id] + elif isinstance(node, NameConstant): + return node.value elif isinstance(node, UnaryOp) and \ isinstance(node.op, (UAdd, USub)) and \ isinstance(node.operand, (Num, UnaryOp, BinOp)): diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py index dc24126b219..36907b4eaa6 100644 --- a/Lib/test/test_ast.py +++ b/Lib/test/test_ast.py @@ -928,6 +928,9 @@ class ASTValidatorTests(unittest.TestCase): def test_tuple(self): self._sequence(ast.Tuple) + def test_nameconstant(self): + self.expr(ast.NameConstant(4), "singleton must be True, False, or None") + def test_stdlib_validates(self): stdlib = os.path.dirname(ast.__file__) tests = [fn for fn in os.listdir(stdlib) if fn.endswith(".py")] @@ -959,13 +962,13 @@ def main(): #### EVERYTHING BELOW IS GENERATED ##### exec_results = [ -('Module', [('Expr', (1, 0), ('Name', (1, 0), 'None', ('Load',)))]), +('Module', [('Expr', (1, 0), ('NameConstant', (1, 0), None))]), ('Module', [('FunctionDef', (1, 0), 'f', ('arguments', [], None, None, [], None, None, [], []), [('Pass', (1, 9))], [], None)]), ('Module', [('FunctionDef', (1, 0), 'f', ('arguments', [('arg', 'a', None)], None, None, [], None, None, [], []), [('Pass', (1, 10))], [], None)]), ('Module', [('FunctionDef', (1, 0), 'f', ('arguments', [('arg', 'a', None)], None, None, [], None, None, [('Num', (1, 8), 0)], []), [('Pass', (1, 12))], [], None)]), ('Module', [('FunctionDef', (1, 0), 'f', ('arguments', [], 'args', None, [], None, None, [], []), [('Pass', (1, 14))], [], None)]), ('Module', [('FunctionDef', (1, 0), 'f', ('arguments', [], None, None, [], 'kwargs', None, [], []), [('Pass', (1, 17))], [], None)]), -('Module', [('FunctionDef', (1, 0), 'f', ('arguments', [('arg', 'a', None), ('arg', 'b', None), ('arg', 'c', None), ('arg', 'd', None), ('arg', 'e', None)], 'args', None, [], 'kwargs', None, [('Num', (1, 11), 1), ('Name', (1, 16), 'None', ('Load',)), ('List', (1, 24), [], ('Load',)), ('Dict', (1, 30), [], [])], []), [('Pass', (1, 52))], [], None)]), +('Module', [('FunctionDef', (1, 0), 'f', ('arguments', [('arg', 'a', None), ('arg', 'b', None), ('arg', 'c', None), ('arg', 'd', None), ('arg', 'e', None)], 'args', None, [], 'kwargs', None, [('Num', (1, 11), 1), ('NameConstant', (1, 16), None), ('List', (1, 24), [], ('Load',)), ('Dict', (1, 30), [], [])], []), [('Pass', (1, 52))], [], None)]), ('Module', [('ClassDef', (1, 0), 'C', [], [], None, None, [('Pass', (1, 8))], [])]), ('Module', [('ClassDef', (1, 0), 'C', [('Name', (1, 8), 'object', ('Load',))], [], None, None, [('Pass', (1, 17))], [])]), ('Module', [('FunctionDef', (1, 0), 'f', ('arguments', [], None, None, [], None, None, [], []), [('Return', (1, 8), ('Num', (1, 15), 1))], [], None)]), @@ -1002,14 +1005,14 @@ single_results = [ ('Interactive', [('Expr', (1, 0), ('BinOp', (1, 0), ('Num', (1, 0), 1), ('Add',), ('Num', (1, 2), 2)))]), ] eval_results = [ -('Expression', ('Name', (1, 0), 'None', ('Load',))), +('Expression', ('NameConstant', (1, 0), None)), ('Expression', ('BoolOp', (1, 0), ('And',), [('Name', (1, 0), 'a', ('Load',)), ('Name', (1, 6), 'b', ('Load',))])), ('Expression', ('BinOp', (1, 0), ('Name', (1, 0), 'a', ('Load',)), ('Add',), ('Name', (1, 4), 'b', ('Load',)))), ('Expression', ('UnaryOp', (1, 0), ('Not',), ('Name', (1, 4), 'v', ('Load',)))), -('Expression', ('Lambda', (1, 0), ('arguments', [], None, None, [], None, None, [], []), ('Name', (1, 7), 'None', ('Load',)))), +('Expression', ('Lambda', (1, 0), ('arguments', [], None, None, [], None, None, [], []), ('NameConstant', (1, 7), None))), ('Expression', ('Dict', (1, 0), [('Num', (1, 2), 1)], [('Num', (1, 4), 2)])), ('Expression', ('Dict', (1, 0), [], [])), -('Expression', ('Set', (1, 0), [('Name', (1, 1), 'None', ('Load',))])), +('Expression', ('Set', (1, 0), [('NameConstant', (1, 1), None)])), ('Expression', ('Dict', (1, 0), [('Num', (2, 6), 1)], [('Num', (4, 10), 2)])), ('Expression', ('ListComp', (1, 1), ('Name', (1, 1), 'a', ('Load',)), [('comprehension', ('Name', (1, 7), 'b', ('Store',)), ('Name', (1, 12), 'c', ('Load',)), [('Name', (1, 17), 'd', ('Load',))])])), ('Expression', ('GeneratorExp', (1, 1), ('Name', (1, 1), 'a', ('Load',)), [('comprehension', ('Name', (1, 7), 'b', ('Store',)), ('Name', (1, 12), 'c', ('Load',)), [('Name', (1, 17), 'd', ('Load',))])])), diff --git a/Lib/test/test_syntax.py b/Lib/test/test_syntax.py index 5926b69c93b..a9d36288195 100644 --- a/Lib/test/test_syntax.py +++ b/Lib/test/test_syntax.py @@ -33,7 +33,7 @@ SyntaxError: invalid syntax >>> None = 1 Traceback (most recent call last): -SyntaxError: assignment to keyword +SyntaxError: can't assign to keyword It's a syntax error to assign to the empty tuple. Why isn't it an error to assign to the empty list? It will always raise some error at @@ -233,7 +233,7 @@ Traceback (most recent call last): SyntaxError: can't assign to generator expression >>> None += 1 Traceback (most recent call last): -SyntaxError: assignment to keyword +SyntaxError: can't assign to keyword >>> f() += 1 Traceback (most recent call last): SyntaxError: can't assign to function call diff --git a/Misc/NEWS b/Misc/NEWS index 6f7308497d6..1f2687a12e1 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -10,6 +10,10 @@ What's New in Python 3.4.0 Alpha 1? Core and Builtins ----------------- +- Issue #16619: Create NameConstant AST class to represent None, True, and False + literals. As a result, these constants are never loaded at runtime from + builtins. + - Issue #16455: On FreeBSD and Solaris, if the locale is C, the ASCII/surrogateescape codec is now used, instead of the locale encoding, to decode the command line arguments. This change fixes inconsistencies with diff --git a/Parser/Python.asdl b/Parser/Python.asdl index c24d8406192..0d373b09d32 100644 --- a/Parser/Python.asdl +++ b/Parser/Python.asdl @@ -1,4 +1,4 @@ --- ASDL's five builtin types are identifier, int, string, bytes, object +-- ASDL's six builtin types are identifier, int, string, bytes, object, singleton module Python { @@ -69,8 +69,8 @@ module Python | Num(object n) -- a number as a PyObject. | Str(string s) -- need to specify raw, unicode, etc? | Bytes(bytes s) + | NameConstant(singleton value) | Ellipsis - -- other literals? bools? -- the following expression can appear in assignment context | Attribute(expr value, identifier attr, expr_context ctx) diff --git a/Parser/asdl.py b/Parser/asdl.py index 08aa05b897c..1f98ada992f 100644 --- a/Parser/asdl.py +++ b/Parser/asdl.py @@ -222,7 +222,7 @@ class ASDLParser(spark.GenericParser, object): " field ::= Id ? " return Field(type[0], opt=True) -builtin_types = ("identifier", "string", "bytes", "int", "object") +builtin_types = ("identifier", "string", "bytes", "int", "object", "singleton") # below is a collection of classes to capture the AST of an AST :-) # not sure if any of the methods are useful yet, but I'm adding them diff --git a/Parser/asdl_c.py b/Parser/asdl_c.py index a9e6626ab41..9557ba0cf2c 100755 --- a/Parser/asdl_c.py +++ b/Parser/asdl_c.py @@ -820,6 +820,7 @@ static PyObject* ast2obj_object(void *o) Py_INCREF((PyObject*)o); return (PyObject*)o; } +#define ast2obj_singleton ast2obj_object #define ast2obj_identifier ast2obj_object #define ast2obj_string ast2obj_object #define ast2obj_bytes ast2obj_object @@ -831,6 +832,17 @@ static PyObject* ast2obj_int(long b) /* Conversion Python -> AST */ +static int obj2ast_singleton(PyObject *obj, PyObject** out, PyArena* arena) +{ + if (obj != Py_None && obj != Py_True && obj != Py_False) { + PyErr_SetString(PyExc_ValueError, + "AST singleton must be True, False, or None"); + return 1; + } + *out = obj; + return 0; +} + static int obj2ast_object(PyObject* obj, PyObject** out, PyArena* arena) { if (obj == Py_None) diff --git a/Python/Python-ast.c b/Python/Python-ast.c index e6f1e58252e..20b7acb8865 100644 --- a/Python/Python-ast.c +++ b/Python/Python-ast.c @@ -271,6 +271,10 @@ static PyTypeObject *Bytes_type; static char *Bytes_fields[]={ "s", }; +static PyTypeObject *NameConstant_type; +static char *NameConstant_fields[]={ + "value", +}; static PyTypeObject *Ellipsis_type; static PyTypeObject *Attribute_type; _Py_IDENTIFIER(attr); @@ -673,6 +677,7 @@ static PyObject* ast2obj_object(void *o) Py_INCREF((PyObject*)o); return (PyObject*)o; } +#define ast2obj_singleton ast2obj_object #define ast2obj_identifier ast2obj_object #define ast2obj_string ast2obj_object #define ast2obj_bytes ast2obj_object @@ -684,6 +689,17 @@ static PyObject* ast2obj_int(long b) /* Conversion Python -> AST */ +static int obj2ast_singleton(PyObject *obj, PyObject** out, PyArena* arena) +{ + if (obj != Py_None && obj != Py_True && obj != Py_False) { + PyErr_SetString(PyExc_ValueError, + "AST singleton must be True, False, or None"); + return 1; + } + *out = obj; + return 0; +} + static int obj2ast_object(PyObject* obj, PyObject** out, PyArena* arena) { if (obj == Py_None) @@ -860,6 +876,9 @@ static int init_types(void) if (!Str_type) return 0; Bytes_type = make_type("Bytes", expr_type, Bytes_fields, 1); if (!Bytes_type) return 0; + NameConstant_type = make_type("NameConstant", expr_type, + NameConstant_fields, 1); + if (!NameConstant_type) return 0; Ellipsis_type = make_type("Ellipsis", expr_type, NULL, 0); if (!Ellipsis_type) return 0; Attribute_type = make_type("Attribute", expr_type, Attribute_fields, 3); @@ -1920,6 +1939,25 @@ Bytes(bytes s, int lineno, int col_offset, PyArena *arena) return p; } +expr_ty +NameConstant(singleton value, int lineno, int col_offset, PyArena *arena) +{ + expr_ty p; + if (!value) { + PyErr_SetString(PyExc_ValueError, + "field value is required for NameConstant"); + return NULL; + } + p = (expr_ty)PyArena_Malloc(arena, sizeof(*p)); + if (!p) + return NULL; + p->kind = NameConstant_kind; + p->v.NameConstant.value = value; + p->lineno = lineno; + p->col_offset = col_offset; + return p; +} + expr_ty Ellipsis(int lineno, int col_offset, PyArena *arena) { @@ -2028,6 +2066,7 @@ Name(identifier id, expr_context_ty ctx, int lineno, int col_offset, PyArena *arena) { expr_ty p; + assert(PyUnicode_CompareWithASCIIString(id, "True") && PyUnicode_CompareWithASCIIString(id, "False") && PyUnicode_CompareWithASCIIString(id, "None")); if (!id) { PyErr_SetString(PyExc_ValueError, "field id is required for Name"); @@ -2948,6 +2987,15 @@ ast2obj_expr(void* _o) goto failed; Py_DECREF(value); break; + case NameConstant_kind: + result = PyType_GenericNew(NameConstant_type, NULL, NULL); + if (!result) goto failed; + value = ast2obj_singleton(o->v.NameConstant.value); + if (!value) goto failed; + if (_PyObject_SetAttrId(result, &PyId_value, value) == -1) + goto failed; + Py_DECREF(value); + break; case Ellipsis_kind: result = PyType_GenericNew(Ellipsis_type, NULL, NULL); if (!result) goto failed; @@ -5688,6 +5736,29 @@ obj2ast_expr(PyObject* obj, expr_ty* out, PyArena* arena) if (*out == NULL) goto failed; return 0; } + isinstance = PyObject_IsInstance(obj, (PyObject*)NameConstant_type); + if (isinstance == -1) { + return 1; + } + if (isinstance) { + singleton value; + + if (_PyObject_HasAttrId(obj, &PyId_value)) { + int res; + tmp = _PyObject_GetAttrId(obj, &PyId_value); + if (tmp == NULL) goto failed; + res = obj2ast_singleton(tmp, &value, arena); + if (res != 0) goto failed; + Py_XDECREF(tmp); + tmp = NULL; + } else { + PyErr_SetString(PyExc_TypeError, "required field \"value\" missing from NameConstant"); + return 1; + } + *out = NameConstant(value, lineno, col_offset, arena); + if (*out == NULL) goto failed; + return 0; + } isinstance = PyObject_IsInstance(obj, (PyObject*)Ellipsis_type); if (isinstance == -1) { return 1; @@ -7008,6 +7079,8 @@ PyInit__ast(void) NULL; if (PyDict_SetItemString(d, "Bytes", (PyObject*)Bytes_type) < 0) return NULL; + if (PyDict_SetItemString(d, "NameConstant", + (PyObject*)NameConstant_type) < 0) return NULL; if (PyDict_SetItemString(d, "Ellipsis", (PyObject*)Ellipsis_type) < 0) return NULL; if (PyDict_SetItemString(d, "Attribute", (PyObject*)Attribute_type) < diff --git a/Python/ast.c b/Python/ast.c index 7657b22459f..50603033d56 100644 --- a/Python/ast.c +++ b/Python/ast.c @@ -282,6 +282,7 @@ validate_expr(expr_ty exp, expr_context_ty ctx) return validate_exprs(exp->v.Tuple.elts, ctx, 0); /* These last cases don't have any checking. */ case Name_kind: + case NameConstant_kind: case Ellipsis_kind: return 1; default: @@ -903,7 +904,7 @@ set_context(struct compiling *c, expr_ty e, expr_context_ty ctx, const node *n) break; case Name_kind: if (ctx == Store) { - if (forbidden_name(c, e->v.Name.id, n, 1)) + if (forbidden_name(c, e->v.Name.id, n, 0)) return 0; /* forbidden_name() calls ast_error() */ } e->v.Name.ctx = ctx; @@ -955,6 +956,9 @@ set_context(struct compiling *c, expr_ty e, expr_context_ty ctx, const node *n) case Bytes_kind: expr_name = "literal"; break; + case NameConstant_kind: + expr_name = "keyword"; + break; case Ellipsis_kind: expr_name = "Ellipsis"; break; @@ -1819,11 +1823,21 @@ ast_for_atom(struct compiling *c, const node *n) switch (TYPE(ch)) { case NAME: { - /* All names start in Load context, but may later be - changed. */ - PyObject *name = NEW_IDENTIFIER(ch); + PyObject *name; + const char *s = STR(ch); + size_t len = strlen(s); + if (len >= 4 && len <= 5) { + if (!strcmp(s, "None")) + return NameConstant(Py_None, LINENO(n), n->n_col_offset, c->c_arena); + if (!strcmp(s, "True")) + return NameConstant(Py_True, LINENO(n), n->n_col_offset, c->c_arena); + if (!strcmp(s, "False")) + return NameConstant(Py_False, LINENO(n), n->n_col_offset, c->c_arena); + } + name = new_identifier(s, c); if (!name) return NULL; + /* All names start in Load context, but may later be changed. */ return Name(name, Load, LINENO(n), n->n_col_offset, c->c_arena); } case STRING: { diff --git a/Python/compile.c b/Python/compile.c index 3cf71ef09e2..3e960ccbfec 100644 --- a/Python/compile.c +++ b/Python/compile.c @@ -3194,12 +3194,18 @@ expr_constant(struct compiler *c, expr_ty e) case Name_kind: /* optimize away names that can't be reassigned */ id = PyUnicode_AsUTF8(e->v.Name.id); - if (strcmp(id, "True") == 0) return 1; - if (strcmp(id, "False") == 0) return 0; - if (strcmp(id, "None") == 0) return 0; - if (strcmp(id, "__debug__") == 0) - return ! c->c_optimize; - /* fall through */ + if (id && strcmp(id, "__debug__") == 0) + return !c->c_optimize; + return -1; + case NameConstant_kind: { + PyObject *o = e->v.NameConstant.value; + if (o == Py_None) + return 0; + else if (o == Py_True) + return 1; + else if (o == Py_False) + return 0; + } default: return -1; } @@ -3375,6 +3381,9 @@ compiler_visit_expr(struct compiler *c, expr_ty e) case Ellipsis_kind: ADDOP_O(c, LOAD_CONST, Py_Ellipsis, consts); break; + case NameConstant_kind: + ADDOP_O(c, LOAD_CONST, e->v.NameConstant.value, consts); + break; /* The following exprs can be assignment targets. */ case Attribute_kind: if (e->v.Attribute.ctx != AugStore) diff --git a/Python/peephole.c b/Python/peephole.c index 5d536779acf..e6877bb3e6a 100644 --- a/Python/peephole.c +++ b/Python/peephole.c @@ -327,37 +327,6 @@ markblocks(unsigned char *code, Py_ssize_t len) return blocks; } -/* Helper to replace LOAD_NAME None/True/False with LOAD_CONST - Returns: 0 if no change, 1 if change, -1 if error */ -static int -load_global(unsigned char *codestr, Py_ssize_t i, char *name, PyObject *consts) -{ - Py_ssize_t j; - PyObject *obj; - if (name == NULL) - return 0; - if (strcmp(name, "None") == 0) - obj = Py_None; - else if (strcmp(name, "True") == 0) - obj = Py_True; - else if (strcmp(name, "False") == 0) - obj = Py_False; - else - return 0; - for (j = 0; j < PyList_GET_SIZE(consts); j++) { - if (PyList_GET_ITEM(consts, j) == obj) - break; - } - if (j == PyList_GET_SIZE(consts)) { - if (PyList_Append(consts, obj) < 0) - return -1; - } - assert(PyList_GET_ITEM(consts, j) == obj); - codestr[i] = LOAD_CONST; - SETARG(codestr, i, j); - return 1; -} - /* Perform basic peephole optimizations to components of a code object. The consts object should still be in list form to allow new constants to be appended. @@ -392,7 +361,6 @@ PyCode_Optimize(PyObject *code, PyObject* consts, PyObject *names, Py_ssize_t const_stack_size = 0; int in_consts = 0; /* whether we are in a LOAD_CONST sequence */ unsigned int *blocks = NULL; - char *name; /* Bail out if an exception is set */ if (PyErr_Occurred()) @@ -475,20 +443,6 @@ PyCode_Optimize(PyObject *code, PyObject* consts, PyObject *names, codestr[i+3] = NOP; break; - /* Replace LOAD_GLOBAL/LOAD_NAME None/True/False - with LOAD_CONST None/True/False */ - case LOAD_NAME: - case LOAD_GLOBAL: - j = GETARG(codestr, i); - name = _PyUnicode_AsString(PyTuple_GET_ITEM(names, j)); - h = load_global(codestr, i, name, consts); - if (h < 0) - goto exitError; - else if (h == 0) - continue; - CONST_STACK_PUSH_OP(i); - break; - /* Skip over LOAD_CONST trueconst POP_JUMP_IF_FALSE xx. This improves "while 1" performance. */ diff --git a/Python/symtable.c b/Python/symtable.c index 8d941f0d549..d16bfbcad34 100644 --- a/Python/symtable.c +++ b/Python/symtable.c @@ -1437,6 +1437,7 @@ symtable_visit_expr(struct symtable *st, expr_ty e) case Str_kind: case Bytes_kind: case Ellipsis_kind: + case NameConstant_kind: /* Nothing to do here. */ break; /* The following exprs can be assignment targets. */ diff --git a/Tools/parser/unparse.py b/Tools/parser/unparse.py index b55e2c6235a..28b2d5bc019 100644 --- a/Tools/parser/unparse.py +++ b/Tools/parser/unparse.py @@ -307,6 +307,9 @@ class Unparser: def _Name(self, t): self.write(t.id) + def _NameConstant(self, t): + self.write(repr(t.value)) + def _Num(self, t): # Substitute overflowing decimal literal for AST infinities. self.write(repr(t.n).replace("inf", INFSTR))