Part way to allowing "from __future__ import generators" to communicate
that info to code dynamically compiled *by* code compiled with generators
enabled. Doesn't yet work because there's still no way to tell the parser
that "yield" is OK (unlike nested_scopes, the parser has its fingers in
this too).
Replaced PyEval_GetNestedScopes by a more-general
PyEval_MergeCompilerFlags. Perhaps I should not have? I doubted it was
*intended* to be part of the public API, so just did.
diff --git a/Include/Python.h b/Include/Python.h
index 5d91125..24d33b2 100644
--- a/Include/Python.h
+++ b/Include/Python.h
@@ -96,8 +96,8 @@
#include "pystate.h"
#include "modsupport.h"
-#include "ceval.h"
#include "pythonrun.h"
+#include "ceval.h"
#include "sysmodule.h"
#include "intrcheck.h"
#include "import.h"
diff --git a/Include/ceval.h b/Include/ceval.h
index 19ac064..0fc5cba 100644
--- a/Include/ceval.h
+++ b/Include/ceval.h
@@ -31,7 +31,11 @@
DL_IMPORT(PyObject *) PyEval_GetOwner(void);
DL_IMPORT(PyObject *) PyEval_GetFrame(void);
DL_IMPORT(int) PyEval_GetRestricted(void);
-DL_IMPORT(int) PyEval_GetNestedScopes(void);
+
+/* Look at the current frame's (if any) code's co_flags, and turn on
+ the corresponding compiler flags in cf->cf_flags. Return 1 if any
+ flag was set, else return 0. */
+DL_IMPORT(int) PyEval_MergeCompilerFlags(PyCompilerFlags *cf);
DL_IMPORT(int) Py_FlushLine(void);
diff --git a/Include/compile.h b/Include/compile.h
index 5e6e572..89c5ba4 100644
--- a/Include/compile.h
+++ b/Include/compile.h
@@ -34,6 +34,13 @@
#define CO_VARKEYWORDS 0x0008
#define CO_NESTED 0x0010
#define CO_GENERATOR 0x0020
+/* XXX Temporary hack. Until generators are a permanent part of the
+ language, we need a way for a code object to record that generators
+ were *possible* when it was compiled. This is so code dynamically
+ compiled *by* a code object knows whether to allow yield stmts. In
+ effect, this passes on the "from __future__ import generators" state
+ in effect when the code block was compiled. */
+#define CO_GENERATOR_ALLOWED 0x1000
extern DL_IMPORT(PyTypeObject) PyCode_Type;
@@ -56,6 +63,7 @@
int ff_found_docstring;
int ff_last_lineno;
int ff_nested_scopes;
+ int ff_generators;
} PyFutureFeatures;
DL_IMPORT(PyFutureFeatures *) PyNode_Future(struct _node *, char *);
diff --git a/Include/pythonrun.h b/Include/pythonrun.h
index e7274ec..3877a82 100644
--- a/Include/pythonrun.h
+++ b/Include/pythonrun.h
@@ -7,8 +7,13 @@
extern "C" {
#endif
+/* These flags are named after the __future__ statements that introduced
+ them. May not remain true for later additions, so fiddle this comment
+ accordingly then. */
+#define PyCF_NESTED_SCOPES (0x00000001UL)
+#define PyCF_GENERATORS (0x00000002UL)
typedef struct {
- int cf_nested_scopes;
+ unsigned long cf_flags; /* bitmask of PyCF_xxx flags */
} PyCompilerFlags;
DL_IMPORT(void) Py_SetProgramName(char *);
diff --git a/Lib/test/test_generators.py b/Lib/test/test_generators.py
index 9aa462f..2a174c3 100644
--- a/Lib/test/test_generators.py
+++ b/Lib/test/test_generators.py
@@ -1,3 +1,5 @@
+from __future__ import generators
+
tutorial_tests = """
Let's try a simple generator:
diff --git a/Modules/main.c b/Modules/main.c
index 64abaf3..3ce83c3 100644
--- a/Modules/main.c
+++ b/Modules/main.c
@@ -298,7 +298,7 @@
Py_DECREF(v);
}
- cf.cf_nested_scopes = 0;
+ cf.cf_flags = 0;
if (command) {
sts = PyRun_SimpleString(command) != 0;
diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
index 11d6f4c..fcc7d17 100644
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -393,6 +393,7 @@
char *filename;
char *startstr;
int start;
+ PyCompilerFlags cf;
if (!PyArg_ParseTuple(args, "sss:compile", &str, &filename, &startstr))
return NULL;
@@ -407,11 +408,10 @@
"compile() arg 3 must be 'exec' or 'eval' or 'single'");
return NULL;
}
- if (PyEval_GetNestedScopes()) {
- PyCompilerFlags cf;
- cf.cf_nested_scopes = 1;
+ cf.cf_flags = 0;
+ if (PyEval_MergeCompilerFlags(&cf))
return Py_CompileStringFlags(str, filename, start, &cf);
- } else
+ else
return Py_CompileString(str, filename, start);
}
@@ -822,6 +822,7 @@
PyObject *globals = Py_None, *locals = Py_None;
PyObject *res;
FILE* fp;
+ PyCompilerFlags cf;
if (!PyArg_ParseTuple(args, "s|O!O!:execfile",
&filename,
@@ -847,12 +848,11 @@
PyErr_SetFromErrno(PyExc_IOError);
return NULL;
}
- if (PyEval_GetNestedScopes()) {
- PyCompilerFlags cf;
- cf.cf_nested_scopes = 1;
+ cf.cf_flags = 0;
+ if (PyEval_MergeCompilerFlags(&cf))
res = PyRun_FileExFlags(fp, filename, Py_file_input, globals,
locals, 1, &cf);
- } else
+ else
res = PyRun_FileEx(fp, filename, Py_file_input, globals,
locals, 1);
return res;
diff --git a/Python/ceval.c b/Python/ceval.c
index f42165e..e614e17 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -2524,7 +2524,7 @@
if (co->co_flags & CO_GENERATOR) {
/* Don't need to keep the reference to f_back, it will be set
* when the generator is resumed. */
- Py_DECREF(f->f_back);
+ Py_XDECREF(f->f_back);
f->f_back = NULL;
/* Create a new generator that owns the ready to run frame
@@ -2906,11 +2906,23 @@
}
int
-PyEval_GetNestedScopes(void)
+PyEval_MergeCompilerFlags(PyCompilerFlags *cf)
{
PyFrameObject *current_frame = PyThreadState_Get()->frame;
- return current_frame == NULL ? 0 :
- current_frame->f_code->co_flags & CO_NESTED;
+ int result = 0;
+
+ if (current_frame != NULL) {
+ const int codeflags = current_frame->f_code->co_flags;
+ if (codeflags & CO_NESTED) {
+ result = 1;
+ cf->cf_flags |= PyCF_NESTED_SCOPES;
+ }
+ if (codeflags & CO_GENERATOR_ALLOWED) {
+ result = 1;
+ cf->cf_flags |= PyCF_GENERATORS;
+ }
+ }
+ return result;
}
int
@@ -3730,26 +3742,25 @@
else if (PyFile_Check(prog)) {
FILE *fp = PyFile_AsFile(prog);
char *name = PyString_AsString(PyFile_Name(prog));
- if (PyEval_GetNestedScopes()) {
- PyCompilerFlags cf;
- cf.cf_nested_scopes = 1;
+ PyCompilerFlags cf;
+ cf.cf_flags = 0;
+ if (PyEval_MergeCompilerFlags(&cf))
v = PyRun_FileFlags(fp, name, Py_file_input, globals,
locals, &cf);
- } else {
+ else
v = PyRun_File(fp, name, Py_file_input, globals,
locals);
- }
}
else {
char *str;
+ PyCompilerFlags cf;
if (PyString_AsStringAndSize(prog, &str, NULL))
return -1;
- if (PyEval_GetNestedScopes()) {
- PyCompilerFlags cf;
- cf.cf_nested_scopes = 1;
+ cf.cf_flags = 0;
+ if (PyEval_MergeCompilerFlags(&cf))
v = PyRun_StringFlags(str, Py_file_input, globals,
locals, &cf);
- } else
+ else
v = PyRun_String(str, Py_file_input, globals, locals);
}
if (plain)
diff --git a/Python/compile.c b/Python/compile.c
index 92322fc..e950f0f 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -3953,10 +3953,15 @@
return NULL;
}
if (flags) {
- if (flags->cf_nested_scopes)
+ if (flags->cf_flags & PyCF_NESTED_SCOPES)
sc.c_future->ff_nested_scopes = 1;
else if (sc.c_future->ff_nested_scopes)
- flags->cf_nested_scopes = 1;
+ flags->cf_flags |= PyCF_NESTED_SCOPES;
+
+ if (flags->cf_flags & PyCF_GENERATORS)
+ sc.c_future->ff_generators = 1;
+ else if (sc.c_future->ff_generators)
+ flags->cf_flags |= PyCF_GENERATORS;
}
if (symtable_build(&sc, n) < 0) {
com_free(&sc);
@@ -4426,8 +4431,12 @@
symtable_update_flags(struct compiling *c, PySymtableEntryObject *ste,
struct symbol_info *si)
{
- if (c->c_future && c->c_future->ff_nested_scopes)
- c->c_flags |= CO_NESTED;
+ if (c->c_future) {
+ if (c->c_future->ff_nested_scopes)
+ c->c_flags |= CO_NESTED;
+ if (c->c_future->ff_generators)
+ c->c_flags |= CO_GENERATOR_ALLOWED;
+ }
if (ste->ste_generator)
c->c_flags |= CO_GENERATOR;
if (ste->ste_type != TYPE_MODULE)
diff --git a/Python/future.c b/Python/future.c
index 70be26b..f0960ae 100644
--- a/Python/future.c
+++ b/Python/future.c
@@ -32,7 +32,7 @@
if (strcmp(feature, FUTURE_NESTED_SCOPES) == 0) {
ff->ff_nested_scopes = 1;
} else if (strcmp(feature, FUTURE_GENERATORS) == 0) {
- /* OK; this is processed by the parser */
+ ff->ff_generators= 1;
} else if (strcmp(feature, "braces") == 0) {
PyErr_SetString(PyExc_SyntaxError,
"not a chance");
@@ -233,6 +233,7 @@
ff->ff_found_docstring = 0;
ff->ff_last_lineno = -1;
ff->ff_nested_scopes = 0;
+ ff->ff_generators = 0;
if (future_parse(ff, n, filename) < 0) {
PyMem_Free((void *)ff);
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index c67f50e..d5705b9 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -494,7 +494,7 @@
if (flags == NULL) {
flags = &local_flags;
- local_flags.cf_nested_scopes = 0;
+ local_flags.cf_flags = 0;
}
v = PySys_GetObject("ps1");
if (v == NULL) {
@@ -1075,10 +1075,14 @@
v = PyEval_EvalCode(co, globals, locals);
if (v && flags) {
if (co->co_flags & CO_NESTED)
- flags->cf_nested_scopes = 1;
+ flags->cf_flags |= PyCF_NESTED_SCOPES;
+ if (co->co_flags & CO_GENERATOR)
+ flags->cf_flags |= PyCF_GENERATORS;
#if 0
fprintf(stderr, "run_pyc_file: nested_scopes: %d\n",
- flags->cf_nested_scopes);
+ flags->cf_flags & PyCF_NESTED_SCOPES);
+ fprintf(stderr, "run_pyc_file: generators: %d\n",
+ flags->cf_flags & PyCF_GENERATORS);
#endif
}
Py_DECREF(co);