/*
pybind11/exec.h: Support for evaluating Python expressions and statements
from strings and files
Copyright (c) 2016 Klemens Morgenstern and
Wenzel Jakob
All rights reserved. Use of this source code is governed by a
BSD-style license that can be found in the LICENSE file.
*/
#pragma once
#include "pybind11.h"
PYBIND11_NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
PYBIND11_NAMESPACE_BEGIN(detail)
inline void ensure_builtins_in_globals(object &global) {
#if PY_VERSION_HEX < 0x03080000
// Running exec and eval on Python 2 and 3 adds `builtins` module under
// `__builtins__` key to globals if not yet present.
// Python 3.8 made PyRun_String behave similarly. Let's also do that for
// older versions, for consistency.
if (!global.contains("__builtins__"))
global["__builtins__"] = module_::import(PYBIND11_BUILTINS_MODULE);
#else
(void) global;
#endif
}
PYBIND11_NAMESPACE_END(detail)
enum eval_mode {
/// Evaluate a string containing an isolated expression
eval_expr,
/// Evaluate a string containing a single statement. Returns \c none
eval_single_statement,
/// Evaluate a string containing a sequence of statement. Returns \c none
eval_statements
};
template
object eval(str expr, object global = globals(), object local = object()) {
if (!local)
local = global;
detail::ensure_builtins_in_globals(global);
/* PyRun_String does not accept a PyObject / encoding specifier,
this seems to be the only alternative */
std::string buffer = "# -*- coding: utf-8 -*-\n" + (std::string) expr;
int start;
switch (mode) {
case eval_expr: start = Py_eval_input; break;
case eval_single_statement: start = Py_single_input; break;
case eval_statements: start = Py_file_input; break;
default: pybind11_fail("invalid evaluation mode");
}
PyObject *result = PyRun_String(buffer.c_str(), start, global.ptr(), local.ptr());
if (!result)
throw error_already_set();
return reinterpret_steal