Apply SF patch #101135, adding 'import module as m' and 'from module import

name as n'. By doing some twists and turns, "as" is not a reserved word.

There is a slight change in semantics for 'from module import name' (it will
now honour the 'global' keyword) but only in cases that are explicitly
undocumented.

Doc/lib/libdis.tex

@@ -301,6 +301,12 @@ is evaluated, the locals are passed to the class definition.
 Returns with TOS to the caller of the function.
 \end{opcodedesc}
 
+\begin{opcodedesc}{IMPORT_STAR}{}
+Loads all symbols not starting with '_' directly from the module TOS
+to the local namespace. The module is popped after loading all names.
+This opcode implements 'from module import *'.
+\begin{opcodedesc}
+
 \begin{opcodedesc}{EXEC_STMT}{}
 Implements \code{exec TOS2,TOS1,TOS}.  The compiler fills
 missing optional parameters with None.
@@ -411,8 +417,9 @@ modifies the name space.
 \end{opcodedesc}
 
 \begin{opcodedesc}{IMPORT_FROM}{namei}
-Imports the attribute \code{co_names[\var{namei}]}.  The module to import
-from is found in TOS and left there.
+Loads the attribute \code{co_names[\var{namei}]} from the module found in
+TOS. The resulting object is pushed onto the stack, to be subsequently
+stored by a \code{STORE_FAST} instruction.
 \end{opcodedesc}
 
 \begin{opcodedesc}{JUMP_FORWARD}{delta}

Doc/ref/ref6.tex

@@ -443,8 +443,9 @@ It continues with the next cycle of the nearest enclosing loop.
 \stindex{import}
 
 \begin{verbatim}
-import_stmt:    "import" module ("," module)* 
-              | "from" module "import" identifier ("," identifier)*
+import_stmt:    "import" module ["as" name] ("," module ["as" name] )* 
+              | "from" module "import" identifier ["as" name]
+                ("," identifier ["as" name] )*
               | "from" module "import" "*" 
 module:         (identifier ".")* identifier
 \end{verbatim}
@@ -496,13 +497,16 @@ begin.
 
 The first form of \keyword{import} statement binds the module name in the
 local namespace to the module object, and then goes on to import the
-next identifier, if any.  The \keyword{from} form does not bind the
-module name: it goes through the list of identifiers, looks each one
-of them up in the module found in step (1), and binds the name in the
-local namespace to the object thus found.  If a name is not found,
+next identifier, if any.  If the module name is followed by \keyword{as},
+the name following \keyword{as} is used as the local name for the module. 
+The \keyword{from} form does not bind the module name: it goes through the
+list of identifiers, looks each one of them up in the module found in step
+(1), and binds the name in the local namespace to the object thus found. 
+Like with the first form of \keyword{import}, an alternate local name can be
+supplied by specifying "\keyword{as} localname".  If a name is not found,
 \exception{ImportError} is raised.  If the list of identifiers is replaced
-by a star (\samp{*}), all names defined in the module are bound,
-except those beginning with an underscore (\character{_}).
+by a star (\samp{*}), all names defined in the module are bound, except
+those beginning with an underscore (\character{_}).
 \indexii{name}{binding}
 \exindex{ImportError}
 

Grammar/Grammar

@@ -41,7 +41,9 @@ break_stmt: 'break'
 continue_stmt: 'continue'
 return_stmt: 'return' [testlist]
 raise_stmt: 'raise' [test [',' test [',' test]]]
-import_stmt: 'import' dotted_name (',' dotted_name)* | 'from' dotted_name 'import' ('*' | NAME (',' NAME)*)
+import_stmt: 'import' dotted_as_name (',' dotted_as_name)* | 'from' dotted_name 'import' ('*' | import_as_name (',' import_as_name)*)
+import_as_name: NAME [NAME NAME]
+dotted_as_name: dotted_name [NAME NAME]
 dotted_name: NAME ('.' NAME)*
 global_stmt: 'global' NAME (',' NAME)*
 #access_stmt: 'access' ('*' | NAME (',' NAME)*) ':' accesstype  (',' accesstype)*

Include/graminit.h

@@ -19,43 +19,45 @@
 #define return_stmt 274
 #define raise_stmt 275
 #define import_stmt 276
-#define dotted_name 277
-#define global_stmt 278
-#define exec_stmt 279
-#define assert_stmt 280
-#define compound_stmt 281
-#define if_stmt 282
-#define while_stmt 283
-#define for_stmt 284
-#define try_stmt 285
-#define except_clause 286
-#define suite 287
-#define test 288
-#define and_test 289
-#define not_test 290
-#define comparison 291
-#define comp_op 292
-#define expr 293
-#define xor_expr 294
-#define and_expr 295
-#define shift_expr 296
-#define arith_expr 297
-#define term 298
-#define factor 299
-#define power 300
-#define atom 301
-#define listmaker 302
-#define lambdef 303
-#define trailer 304
-#define subscriptlist 305
-#define subscript 306
-#define sliceop 307
-#define exprlist 308
-#define testlist 309
-#define dictmaker 310
-#define classdef 311
-#define arglist 312
-#define argument 313
-#define list_iter 314
-#define list_for 315
-#define list_if 316
+#define import_as_name 277
+#define dotted_as_name 278
+#define dotted_name 279
+#define global_stmt 280
+#define exec_stmt 281
+#define assert_stmt 282
+#define compound_stmt 283
+#define if_stmt 284
+#define while_stmt 285
+#define for_stmt 286
+#define try_stmt 287
+#define except_clause 288
+#define suite 289
+#define test 290
+#define and_test 291
+#define not_test 292
+#define comparison 293
+#define comp_op 294
+#define expr 295
+#define xor_expr 296
+#define and_expr 297
+#define shift_expr 298
+#define arith_expr 299
+#define term 300
+#define factor 301
+#define power 302
+#define atom 303
+#define listmaker 304
+#define lambdef 305
+#define trailer 306
+#define subscriptlist 307
+#define subscript 308
+#define sliceop 309
+#define exprlist 310
+#define testlist 311
+#define dictmaker 312
+#define classdef 313
+#define arglist 314
+#define argument 315
+#define list_iter 316
+#define list_for 317
+#define list_if 318

Include/opcode.h

@@ -65,7 +65,7 @@ redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 
 #define LOAD_LOCALS	82
 #define RETURN_VALUE	83
-
+#define IMPORT_STAR	84
 #define EXEC_STMT	85
 
 #define POP_BLOCK	87

Lib/dis.py

@@ -195,7 +195,7 @@ def_op('BREAK_LOOP', 80)
 
 def_op('LOAD_LOCALS', 82)
 def_op('RETURN_VALUE', 83)
-
+def_op('IMPORT_STAR', 84)
 def_op('EXEC_STMT', 85)
 
 def_op('POP_BLOCK', 87)

Lib/test/output/test_pkg

@@ -36,3 +36,10 @@ t6.ham loading
 t6.eggs loading
 ['__all__', '__builtins__', '__doc__', '__file__', '__name__', '__path__', 'eggs', 'ham', 'spam']
 ['eggs', 'ham', 'spam', 't6']
+running test t7
+t7 loading
+['__builtins__', '__doc__', '__file__', '__name__', '__path__']
+['__builtins__', '__doc__', '__file__', '__name__', '__path__']
+t7.sub.subsub loading
+['__builtins__', '__doc__', '__file__', '__name__', '__path__', 'spam']
+t7.sub.subsub.spam = 1

Lib/test/test_pkg.py

@@ -164,6 +164,33 @@ print dir(t6)
 from t6 import *
 print dir(t6)
 print dir()
+"""),
+    
+    ("t7", [
+    ("t7.py", "print 'Importing t7.py'"),
+    ("t7", None),
+    ("t7 __init__.py", "print __name__, 'loading'"),
+    ("t7 sub.py", "print 'THIS SHOULD NOT BE PRINTED (sub.py)'"),
+    ("t7 sub", None),
+    ("t7 sub __init__.py", ""),
+    ("t7 sub subsub.py", "print 'THIS SHOULD NOT BE PRINTED (subsub.py)'"),
+    ("t7 sub subsub", None),
+    ("t7 sub subsub __init__.py", "print __name__, 'loading'; spam = 1"),
+    ],
+"""
+t7, sub, subsub = None, None, None
+import t7 as tas
+print dir(tas)
+assert not t7
+from t7 import sub as subpar
+print dir(subpar)
+assert not t7 and not sub
+from t7.sub import subsub as subsubsub
+print dir(subsubsub)
+assert not t7 and not sub and not subsub
+from t7.sub.subsub import spam as ham
+print "t7.sub.subsub.spam =", ham
+assert not t7 and not sub and not subsub
 """),
 
 ]

Python/ceval.c

@@ -66,7 +66,8 @@ static PyObject *apply_slice(PyObject *, PyObject *, PyObject *);
 static int assign_slice(PyObject *, PyObject *,
 			PyObject *, PyObject *);
 static PyObject *cmp_outcome(int, PyObject *, PyObject *);
-static int import_from(PyObject *, PyObject *, PyObject *);
+static PyObject *import_from(PyObject *, PyObject *);
+static int import_all_from(PyObject *, PyObject *);
 static PyObject *build_class(PyObject *, PyObject *, PyObject *);
 static int exec_statement(PyFrameObject *,
 			  PyObject *, PyObject *, PyObject *);
@@ -1414,20 +1415,28 @@ eval_code2(PyCodeObject *co, PyObject *globals, PyObject *locals,
 			if (x != NULL) continue;
 			break;
 		
-		case IMPORT_FROM:
-			w = GETNAMEV(oparg);
-			v = TOP();
+		case IMPORT_STAR:
+			v = POP();
 			PyFrame_FastToLocals(f);
 			if ((x = f->f_locals) == NULL) {
 				PyErr_SetString(PyExc_SystemError,
 						"no locals");
 				break;
 			}
-			err = import_from(x, v, w);
+			err = import_all_from(x, v);
 			PyFrame_LocalsToFast(f, 0);
+			Py_DECREF(v);
 			if (err == 0) continue;
 			break;
 
+		case IMPORT_FROM:
+			w = GETNAMEV(oparg);
+			v = TOP();
+			x = import_from(v, w);
+			PUSH(x);
+			if (x != NULL) continue;
+			break;
+
 		case JUMP_FORWARD:
 			JUMPBY(oparg);
 			continue;
@@ -2647,43 +2656,51 @@ cmp_outcome(int op, register PyObject *v, register PyObject *w)
 	return v;
 }
 
-static int
-import_from(PyObject *locals, PyObject *v, PyObject *name)
+static PyObject *
+import_from(PyObject *v, PyObject *name)
 {
 	PyObject *w, *x;
+	if (!PyModule_Check(v)) {
+		PyErr_SetString(PyExc_TypeError,
+				"import-from requires module object");
+		return NULL;
+	}
+	w = PyModule_GetDict(v); /* TDB: can this not fail ? */
+	x = PyDict_GetItem(w, name);
+	if (x == NULL) {
+		PyErr_Format(PyExc_ImportError,
+			     "cannot import name %.230s",
+			     PyString_AsString(name));
+	} else
+		Py_INCREF(x);
+	return x;
+}
+
+static int
+import_all_from(PyObject *locals, PyObject *v)
+{
+	int pos = 0, err;
+	PyObject *name, *value;
+	PyObject *w;
+
 	if (!PyModule_Check(v)) {
 		PyErr_SetString(PyExc_TypeError,
 				"import-from requires module object");
 		return -1;
 	}
-	w = PyModule_GetDict(v);
-	if (PyString_AsString(name)[0] == '*') {
-		int pos, err;
-		PyObject *name, *value;
-		pos = 0;
-		while (PyDict_Next(w, &pos, &name, &value)) {
-			if (!PyString_Check(name) ||
-			    PyString_AsString(name)[0] == '_')
+	w = PyModule_GetDict(v); /* TBD: can this not fail ? */
+
+	while (PyDict_Next(w, &pos, &name, &value)) {
+		if (!PyString_Check(name) ||
+			PyString_AsString(name)[0] == '_')
 				continue;
-			Py_INCREF(value);
-			err = PyDict_SetItem(locals, name, value);
-			Py_DECREF(value);
-			if (err != 0)
-				return -1;
-		}
-		return 0;
-	}
-	else {
-		x = PyDict_GetItem(w, name);
-		if (x == NULL) {
-			PyErr_Format(PyExc_ImportError, 
-				     "cannot import name %.230s",
-				     PyString_AsString(name));
+		Py_INCREF(value);
+		err = PyDict_SetItem(locals, name, value);
+		Py_DECREF(value);
+		if (err != 0)
 			return -1;
-		}
-		else
-			return PyDict_SetItem(locals, name, x);
 	}
+	return 0;
 }
 
 static PyObject *
@@ -2825,7 +2842,7 @@ find_from_args(PyFrameObject *f, int nexti)
 	next_instr += nexti;
 
 	opcode = (*next_instr++);
-	if (opcode != IMPORT_FROM) {
+	if (opcode != IMPORT_FROM && opcode != IMPORT_STAR) {
 		Py_INCREF(Py_None);
 		return Py_None;
 	}
@@ -2833,18 +2850,28 @@ find_from_args(PyFrameObject *f, int nexti)
 	list = PyList_New(0);
 	if (list == NULL)
 		return NULL;
-	
-	do {
-		oparg = (next_instr[1]<<8) + next_instr[0];
-		next_instr += 2;
-		name = Getnamev(f, oparg);
-		if (PyList_Append(list, name) < 0) {
+
+	if (opcode == IMPORT_STAR) {
+		name = PyString_FromString("*");
+		if (!name)
 			Py_DECREF(list);
-			break;
+		else {
+			if (PyList_Append(list, name) < 0)
+				Py_DECREF(list);
+			Py_DECREF(name);
 		}
-		opcode = (*next_instr++);
-	} while (opcode == IMPORT_FROM);
-	
+	} else {
+		do {
+			oparg = (next_instr[1]<<8) + next_instr[0];
+			next_instr += 2;
+			name = Getnamev(f, oparg);
+			if (PyList_Append(list, name) < 0) {
+				Py_DECREF(list);
+				break;
+			}
+			opcode = (*next_instr++);
+		} while (opcode == IMPORT_FROM);
+	}
 	return list;
 }
 

Python/compile.c

@@ -2095,6 +2095,22 @@ com_raise_stmt(struct compiling *c, node *n)
 	com_pop(c, i);
 }
 
+static void
+com_from_import(struct compiling *c, node *n)
+{
+	com_addopname(c, IMPORT_FROM, CHILD(n, 0));
+	com_push(c, 1);
+	if (NCH(n) > 1) {
+		if (strcmp(STR(CHILD(n, 1)), "as") != 0) {
+			com_error(c, PyExc_SyntaxError, "invalid syntax");
+			return;
+		}
+		com_addopname(c, STORE_NAME, CHILD(n, 2));
+	} else
+		com_addopname(c, STORE_NAME, CHILD(n, 0));
+	com_pop(c, 1);
+}
+
 static void
 com_import_stmt(struct compiling *c, node *n)
 {
@@ -2107,18 +2123,32 @@ com_import_stmt(struct compiling *c, node *n)
 		REQ(CHILD(n, 1), dotted_name);
 		com_addopname(c, IMPORT_NAME, CHILD(n, 1));
 		com_push(c, 1);
-		for (i = 3; i < NCH(n); i += 2)
-			com_addopname(c, IMPORT_FROM, CHILD(n, i));
-		com_addbyte(c, POP_TOP);
+		if (TYPE(CHILD(n, 3)) == STAR) 
+			com_addbyte(c, IMPORT_STAR);
+		else {
+			for (i = 3; i < NCH(n); i += 2) 
+				com_from_import(c, CHILD(n, i));
+			com_addbyte(c, POP_TOP);
+		}
 		com_pop(c, 1);
 	}
 	else {
 		/* 'import' ... */
 		for (i = 1; i < NCH(n); i += 2) {
-			REQ(CHILD(n, i), dotted_name);
-			com_addopname(c, IMPORT_NAME, CHILD(n, i));
+			node *subn = CHILD(n, i);
+			REQ(subn, dotted_as_name);
+			com_addopname(c, IMPORT_NAME, CHILD(subn, 0));
 			com_push(c, 1);
-			com_addopname(c, STORE_NAME, CHILD(CHILD(n, i), 0));
+			if (NCH(subn) > 1) {
+				if (strcmp(STR(CHILD(subn, 1)), "as") != 0) {
+					com_error(c, PyExc_SyntaxError,
+						  "invalid syntax");
+					return;
+				}
+				com_addopname(c, STORE_NAME, CHILD(subn, 2));
+			} else
+				com_addopname(c, STORE_NAME,
+					      CHILD(CHILD(subn, 0),0));
 			com_pop(c, 1);
 		}
 	}
@@ -3295,12 +3325,14 @@ optimize(struct compiling *c)
 		case IMPORT_FROM:
 			com_addlocal_o(c, GETNAMEOBJ(oparg));
 			break;
+		case IMPORT_STAR:
 		case EXEC_STMT:
 			c->c_flags &= ~CO_OPTIMIZED;
 			break;
 		}
 	}
 	
+	/* TBD: Is this still necessary ? */
 	if (PyDict_GetItemString(c->c_locals, "*") != NULL)
 		c->c_flags &= ~CO_OPTIMIZED;
 	

Python/import.c

@@ -66,7 +66,7 @@ extern time_t PyOS_GetLastModificationTime(char *, FILE *);
 /* XXX Perhaps the magic number should be frozen and a version field
    added to the .pyc file header? */
 /* New way to come up with the magic number: (YEAR-1995), MONTH, DAY */
-#define MAGIC (50811 | ((long)'\r'<<16) | ((long)'\n'<<24))
+#define MAGIC (50815 | ((long)'\r'<<16) | ((long)'\n'<<24))
 
 /* Magic word as global; note that _PyImport_Init() can change the
    value of this global to accommodate for alterations of how the