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Commit f68f2fe

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Moshe Zadka
committed
Implementation of PEP-0217.
This closes the PEP, and patch 103170
1 parent 5ac9795 commit f68f2fe

3 files changed

Lines changed: 72 additions & 27 deletions

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‎Doc/lib/libsys.tex‎

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Original file line numberDiff line numberDiff line change
@@ -44,6 +44,15 @@ \section{\module{sys} ---
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Availability: Windows.
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\end{datadesc}
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\begin{funcdesc}{displayhook}{\var{value}}
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If \var{value} is not \code{None}, this function prints it to
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\code{sys.stdout}, and saves it in \code{__builtin__._}.
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This function is called when an expression is entered at the prompt
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of an interactive Python session. It exists mainly so it can be
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overridden.
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\end{funcdesc}
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\begin{funcdesc}{exc_info}{}
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This function returns a tuple of three values that give information
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about the exception that is currently being handled. The information

‎Python/ceval.c‎

Lines changed: 17 additions & 27 deletions
Original file line numberDiff line numberDiff line change
@@ -1245,36 +1245,26 @@ eval_code2(PyCodeObject *co, PyObject *globals, PyObject *locals,
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case PRINT_EXPR:
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v = POP();
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/* Print value except if None */
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/* After printing, also assign to '_' */
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/* Before, set '_' to None to avoid recursion */
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if (v != Py_None &&
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(err = PyDict_SetItemString(
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f->f_builtins, "_", Py_None)) == 0) {
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err = Py_FlushLine();
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if (err == 0) {
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x = PySys_GetObject("stdout");
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if (x == NULL) {
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PyErr_SetString(
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PyExc_RuntimeError,
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"lost sys.stdout");
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err = -1;
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}
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}
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if (err == 0)
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err = PyFile_WriteObject(v, x, 0);
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if (err == 0) {
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PyFile_SoftSpace(x, 1);
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err = Py_FlushLine();
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}
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if (err == 0) {
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err = PyDict_SetItemString(
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f->f_builtins, "_", v);
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}
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w = PySys_GetObject("displayhook");
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if (w == NULL) {
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PyErr_SetString(PyExc_RuntimeError,
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"lost sys.displayhook");
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err = -1;
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}
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if (err == 0) {
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x = Py_BuildValue("(O)", v);
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if (x == NULL)
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err = -1;
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}
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if (err == 0) {
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w = PyEval_CallObject(w, x);
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if (w == NULL)
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err = -1;
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}
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Py_DECREF(v);
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Py_XDECREF(x);
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break;
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case PRINT_ITEM_TO:
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w = stream = POP();
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/* fall through to PRINT_ITEM */

‎Python/sysmodule.c‎

Lines changed: 46 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -67,6 +67,50 @@ PySys_SetObject(char *name, PyObject *v)
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return PyDict_SetItemString(sd, name, v);
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}
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static PyObject *
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sys_displayhook(PyObject *self, PyObject *args)
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{
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PyObject *o, *stdout;
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PyInterpreterState *interp = PyThreadState_Get()->interp;
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PyObject *modules = interp->modules;
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PyObject *builtins = PyDict_GetItemString(modules, "__builtin__");
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/* parse arguments */
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if (!PyArg_ParseTuple(args, "O:displayhook", &o))
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return NULL;
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/* Print value except if None */
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/* After printing, also assign to '_' */
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/* Before, set '_' to None to avoid recursion */
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if (o == Py_None) {
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Py_INCREF(Py_None);
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return Py_None;
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}
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if (PyObject_SetAttrString(builtins, "_", Py_None) != 0)
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return NULL;
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if (Py_FlushLine() != 0)
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return NULL;
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stdout = PySys_GetObject("stdout");
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if (stdout == NULL) {
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PyErr_SetString(PyExc_RuntimeError, "lost sys.stdout");
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return NULL;
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}
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if (PyFile_WriteObject(o, stdout, 0) != 0)
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return NULL;
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PyFile_SoftSpace(stdout, 1);
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if (Py_FlushLine() != 0)
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return NULL;
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if (PyObject_SetAttrString(builtins, "_", o) != 0)
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return NULL;
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Py_INCREF(Py_None);
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return Py_None;
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}
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static char displayhook_doc[] =
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"displayhook(o) -> None\n"
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"\n"
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"Print o to the stdout, and save it in __builtin__._\n";
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70114
static PyObject *
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sys_exc_info(PyObject *self, PyObject *args)
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{
@@ -332,6 +376,7 @@ extern PyObject *_Py_GetDXProfile(PyObject *, PyObject *);
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static PyMethodDef sys_methods[] = {
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/* Might as well keep this in alphabetic order */
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{"displayhook", sys_displayhook, 1, displayhook_doc},
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{"exc_info", sys_exc_info, 1, exc_info_doc},
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{"exit", sys_exit, 0, exit_doc},
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{"getdefaultencoding", sys_getdefaultencoding, 1,
@@ -475,6 +520,7 @@ __stderr__ -- the original stderr; don't use!\n\
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\n\
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Functions:\n\
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\n\
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displayhook() -- print an object to the screen, and save it in __builtin__._\n\
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exc_info() -- return thread-safe information about the current exception\n\
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exit() -- exit the interpreter by raising SystemExit\n\
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getrefcount() -- return the reference count for an object (plus one :-)\n\

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