The Very High Level Layer¶
The functions in this chapter will let you execute Python source code given in a file or a buffer, but they will not let you interact in a more detailed way with the interpreter.
Several of these functions accept a start symbol from the grammar as a
parameter. The available start symbols are Py_eval_input
,
Py_file_input
, and Py_single_input
. These are described
following the functions which accept them as parameters.
Note also that several of these functions take FILE*
parameters. One
particular issue which needs to be handled carefully is that the FILE
structure for different C libraries can be different and incompatible. Under
Windows (at least), it is possible for dynamically linked extensions to actually
use different libraries, so care should be taken that FILE*
parameters
are only passed to these functions if it is certain that they were created by
the same library that the Python runtime is using.
-
int
Py_Main
(int argc, wchar_t **argv)¶ The main program for the standard interpreter. This is made available for programs which embed Python. The argc and argv parameters should be prepared exactly as those which are passed to a C program’s
main()
function (converted to wchar_t according to the user’s locale). It is important to note that the argument list may be modified (but the contents of the strings pointed to by the argument list are not). The return value will be0
if the interpreter exits normally (i.e., without an exception),1
if the interpreter exits due to an exception, or2
if the parameter list does not represent a valid Python command line.Note that if an otherwise unhandled
SystemExit
is raised, this function will not return1
, but exit the process, as long asPy_InspectFlag
is not set.
-
int
Py_BytesMain
(int argc, char **argv)¶ Similar to
Py_Main()
but argv is an array of bytes strings.Nowe w wersji 3.8.
-
int
PyRun_AnyFile
(FILE *fp, const char *filename)¶ This is a simplified interface to
PyRun_AnyFileExFlags()
below, leaving closeit set to0
and flags set toNULL
.
-
int
PyRun_AnyFileFlags
(FILE *fp, const char *filename, PyCompilerFlags *flags)¶ This is a simplified interface to
PyRun_AnyFileExFlags()
below, leaving the closeit argument set to0
.
-
int
PyRun_AnyFileEx
(FILE *fp, const char *filename, int closeit)¶ This is a simplified interface to
PyRun_AnyFileExFlags()
below, leaving the flags argument set toNULL
.
-
int
PyRun_AnyFileExFlags
(FILE *fp, const char *filename, int closeit, PyCompilerFlags *flags)¶ If fp refers to a file associated with an interactive device (console or terminal input or Unix pseudo-terminal), return the value of
PyRun_InteractiveLoop()
, otherwise return the result ofPyRun_SimpleFile()
. filename is decoded from the filesystem encoding (sys.getfilesystemencoding()
). If filename isNULL
, this function uses"???"
as the filename. If closeit is true, the file is closed beforePyRun_SimpleFileExFlags()
returns.
-
int
PyRun_SimpleString
(const char *command)¶ This is a simplified interface to
PyRun_SimpleStringFlags()
below, leaving thePyCompilerFlags
* argument set toNULL
.
-
int
PyRun_SimpleStringFlags
(const char *command, PyCompilerFlags *flags)¶ Executes the Python source code from command in the
__main__
module according to the flags argument. If__main__
does not already exist, it is created. Returns0
on success or-1
if an exception was raised. If there was an error, there is no way to get the exception information. For the meaning of flags, see below.Note that if an otherwise unhandled
SystemExit
is raised, this function will not return-1
, but exit the process, as long asPy_InspectFlag
is not set.
-
int
PyRun_SimpleFile
(FILE *fp, const char *filename)¶ This is a simplified interface to
PyRun_SimpleFileExFlags()
below, leaving closeit set to0
and flags set toNULL
.
-
int
PyRun_SimpleFileEx
(FILE *fp, const char *filename, int closeit)¶ This is a simplified interface to
PyRun_SimpleFileExFlags()
below, leaving flags set toNULL
.
-
int
PyRun_SimpleFileExFlags
(FILE *fp, const char *filename, int closeit, PyCompilerFlags *flags)¶ Similar to
PyRun_SimpleStringFlags()
, but the Python source code is read from fp instead of an in-memory string. filename should be the name of the file, it is decoded from the filesystem encoding (sys.getfilesystemencoding()
). If closeit is true, the file is closed before PyRun_SimpleFileExFlags returns.Informacja
On Windows, fp should be opened as binary mode (e.g.
fopen(filename, "rb")
). Otherwise, Python may not handle script file with LF line ending correctly.
-
int
PyRun_InteractiveOne
(FILE *fp, const char *filename)¶ This is a simplified interface to
PyRun_InteractiveOneFlags()
below, leaving flags set toNULL
.
-
int
PyRun_InteractiveOneFlags
(FILE *fp, const char *filename, PyCompilerFlags *flags)¶ Read and execute a single statement from a file associated with an interactive device according to the flags argument. The user will be prompted using
sys.ps1
andsys.ps2
. filename is decoded from the filesystem encoding (sys.getfilesystemencoding()
).Returns
0
when the input was executed successfully,-1
if there was an exception, or an error code from theerrcode.h
include file distributed as part of Python if there was a parse error. (Note thaterrcode.h
is not included byPython.h
, so must be included specifically if needed.)
-
int
PyRun_InteractiveLoop
(FILE *fp, const char *filename)¶ This is a simplified interface to
PyRun_InteractiveLoopFlags()
below, leaving flags set toNULL
.
-
int
PyRun_InteractiveLoopFlags
(FILE *fp, const char *filename, PyCompilerFlags *flags)¶ Read and execute statements from a file associated with an interactive device until EOF is reached. The user will be prompted using
sys.ps1
andsys.ps2
. filename is decoded from the filesystem encoding (sys.getfilesystemencoding()
). Returns0
at EOF or a negative number upon failure.
-
int
(*PyOS_InputHook)
(void)¶ Can be set to point to a function with the prototype
int func(void)
. The function will be called when Python’s interpreter prompt is about to become idle and wait for user input from the terminal. The return value is ignored. Overriding this hook can be used to integrate the interpreter’s prompt with other event loops, as done in theModules/_tkinter.c
in the Python source code.
-
char*
(*PyOS_ReadlineFunctionPointer)
(FILE *, FILE *, const char *)¶ Can be set to point to a function with the prototype
char *func(FILE *stdin, FILE *stdout, char *prompt)
, overriding the default function used to read a single line of input at the interpreter’s prompt. The function is expected to output the string prompt if it’s notNULL
, and then read a line of input from the provided standard input file, returning the resulting string. For example, Thereadline
module sets this hook to provide line-editing and tab-completion features.The result must be a string allocated by
PyMem_RawMalloc()
orPyMem_RawRealloc()
, orNULL
if an error occurred.Zmienione w wersji 3.4: The result must be allocated by
PyMem_RawMalloc()
orPyMem_RawRealloc()
, instead of being allocated byPyMem_Malloc()
orPyMem_Realloc()
.
-
struct _node*
PyParser_SimpleParseString
(const char *str, int start)¶ This is a simplified interface to
PyParser_SimpleParseStringFlagsFilename()
below, leaving filename set toNULL
and flags set to0
.Deprecated since version 3.9, will be removed in version 3.10.
-
struct _node*
PyParser_SimpleParseStringFlags
(const char *str, int start, int flags)¶ This is a simplified interface to
PyParser_SimpleParseStringFlagsFilename()
below, leaving filename set toNULL
.Deprecated since version 3.9, will be removed in version 3.10.
-
struct _node*
PyParser_SimpleParseStringFlagsFilename
(const char *str, const char *filename, int start, int flags)¶ Parse Python source code from str using the start token start according to the flags argument. The result can be used to create a code object which can be evaluated efficiently. This is useful if a code fragment must be evaluated many times. filename is decoded from the filesystem encoding (
sys.getfilesystemencoding()
).Deprecated since version 3.9, will be removed in version 3.10.
-
struct _node*
PyParser_SimpleParseFile
(FILE *fp, const char *filename, int start)¶ This is a simplified interface to
PyParser_SimpleParseFileFlags()
below, leaving flags set to0
.Deprecated since version 3.9, will be removed in version 3.10.
-
struct _node*
PyParser_SimpleParseFileFlags
(FILE *fp, const char *filename, int start, int flags)¶ Similar to
PyParser_SimpleParseStringFlagsFilename()
, but the Python source code is read from fp instead of an in-memory string.Deprecated since version 3.9, will be removed in version 3.10.
-
PyObject*
PyRun_String
(const char *str, int start, PyObject *globals, PyObject *locals)¶ - Return value: New reference.
This is a simplified interface to
PyRun_StringFlags()
below, leaving flags set toNULL
.
-
PyObject*
PyRun_StringFlags
(const char *str, int start, PyObject *globals, PyObject *locals, PyCompilerFlags *flags)¶ - Return value: New reference.
Execute Python source code from str in the context specified by the objects globals and locals with the compiler flags specified by flags. globals must be a dictionary; locals can be any object that implements the mapping protocol. The parameter start specifies the start token that should be used to parse the source code.
Returns the result of executing the code as a Python object, or
NULL
if an exception was raised.
-
PyObject*
PyRun_File
(FILE *fp, const char *filename, int start, PyObject *globals, PyObject *locals)¶ - Return value: New reference.
This is a simplified interface to
PyRun_FileExFlags()
below, leaving closeit set to0
and flags set toNULL
.
-
PyObject*
PyRun_FileEx
(FILE *fp, const char *filename, int start, PyObject *globals, PyObject *locals, int closeit)¶ - Return value: New reference.
This is a simplified interface to
PyRun_FileExFlags()
below, leaving flags set toNULL
.
-
PyObject*
PyRun_FileFlags
(FILE *fp, const char *filename, int start, PyObject *globals, PyObject *locals, PyCompilerFlags *flags)¶ - Return value: New reference.
This is a simplified interface to
PyRun_FileExFlags()
below, leaving closeit set to0
.
-
PyObject*
PyRun_FileExFlags
(FILE *fp, const char *filename, int start, PyObject *globals, PyObject *locals, int closeit, PyCompilerFlags *flags)¶ - Return value: New reference.
Similar to
PyRun_StringFlags()
, but the Python source code is read from fp instead of an in-memory string. filename should be the name of the file, it is decoded from the filesystem encoding (sys.getfilesystemencoding()
). If closeit is true, the file is closed beforePyRun_FileExFlags()
returns.
-
PyObject*
Py_CompileString
(const char *str, const char *filename, int start)¶ - Return value: New reference.
This is a simplified interface to
Py_CompileStringFlags()
below, leaving flags set toNULL
.
-
PyObject*
Py_CompileStringFlags
(const char *str, const char *filename, int start, PyCompilerFlags *flags)¶ - Return value: New reference.
This is a simplified interface to
Py_CompileStringExFlags()
below, with optimize set to-1
.
-
PyObject*
Py_CompileStringObject
(const char *str, PyObject *filename, int start, PyCompilerFlags *flags, int optimize)¶ - Return value: New reference.
Parse and compile the Python source code in str, returning the resulting code object. The start token is given by start; this can be used to constrain the code which can be compiled and should be
Py_eval_input
,Py_file_input
, orPy_single_input
. The filename specified by filename is used to construct the code object and may appear in tracebacks orSyntaxError
exception messages. This returnsNULL
if the code cannot be parsed or compiled.The integer optimize specifies the optimization level of the compiler; a value of
-1
selects the optimization level of the interpreter as given by-O
options. Explicit levels are0
(no optimization;__debug__
is true),1
(asserts are removed,__debug__
is false) or2
(docstrings are removed too).Nowe w wersji 3.4.
-
PyObject*
Py_CompileStringExFlags
(const char *str, const char *filename, int start, PyCompilerFlags *flags, int optimize)¶ - Return value: New reference.
Like
Py_CompileStringObject()
, but filename is a byte string decoded from the filesystem encoding (os.fsdecode()
).Nowe w wersji 3.2.
-
PyObject*
PyEval_EvalCode
(PyObject *co, PyObject *globals, PyObject *locals)¶ - Return value: New reference.
This is a simplified interface to
PyEval_EvalCodeEx()
, with just the code object, and global and local variables. The other arguments are set toNULL
.
-
PyObject*
PyEval_EvalCodeEx
(PyObject *co, PyObject *globals, PyObject *locals, PyObject *const *args, int argcount, PyObject *const *kws, int kwcount, PyObject *const *defs, int defcount, PyObject *kwdefs, PyObject *closure)¶ - Return value: New reference.
Evaluate a precompiled code object, given a particular environment for its evaluation. This environment consists of a dictionary of global variables, a mapping object of local variables, arrays of arguments, keywords and defaults, a dictionary of default values for keyword-only arguments and a closure tuple of cells.
-
PyFrameObject
¶ The C structure of the objects used to describe frame objects. The fields of this type are subject to change at any time.
-
PyObject*
PyEval_EvalFrame
(PyFrameObject *f)¶ - Return value: New reference.
Evaluate an execution frame. This is a simplified interface to
PyEval_EvalFrameEx()
, for backward compatibility.
-
PyObject*
PyEval_EvalFrameEx
(PyFrameObject *f, int throwflag)¶ - Return value: New reference.
This is the main, unvarnished function of Python interpretation. The code object associated with the execution frame f is executed, interpreting bytecode and executing calls as needed. The additional throwflag parameter can mostly be ignored - if true, then it causes an exception to immediately be thrown; this is used for the
throw()
methods of generator objects.Zmienione w wersji 3.4: This function now includes a debug assertion to help ensure that it does not silently discard an active exception.
-
int
PyEval_MergeCompilerFlags
(PyCompilerFlags *cf)¶ This function changes the flags of the current evaluation frame, and returns true on success, false on failure.
-
int
Py_eval_input
¶ The start symbol from the Python grammar for isolated expressions; for use with
Py_CompileString()
.
-
int
Py_file_input
¶ The start symbol from the Python grammar for sequences of statements as read from a file or other source; for use with
Py_CompileString()
. This is the symbol to use when compiling arbitrarily long Python source code.
-
int
Py_single_input
¶ The start symbol from the Python grammar for a single statement; for use with
Py_CompileString()
. This is the symbol used for the interactive interpreter loop.
-
struct
PyCompilerFlags
¶ This is the structure used to hold compiler flags. In cases where code is only being compiled, it is passed as
int flags
, and in cases where code is being executed, it is passed asPyCompilerFlags *flags
. In this case,from __future__ import
can modify flags.Whenever
PyCompilerFlags *flags
isNULL
,cf_flags
is treated as equal to0
, and any modification due tofrom __future__ import
is discarded.-
int
cf_flags
¶ Compiler flags.
-
int
cf_feature_version
¶ cf_feature_version is the minor Python version. It should be initialized to
PY_MINOR_VERSION
.The field is ignored by default, it is used if and only if
PyCF_ONLY_AST
flag is set in cf_flags.
Zmienione w wersji 3.8: Added cf_feature_version field.
-
int