[python] added skeleton for python interface

2019-08-15 20:50:10 -07:00
parent 3ece461ce2
commit 4de22df930
47 changed files with 13251 additions and 1951 deletions
--- a/python/src/pybind11/eval.h
+++ b/python/src/pybind11/eval.h
@@ -0,0 +1,117 @@
+/*
+    pybind11/exec.h: Support for evaluating Python expressions and statements
+    from strings and files
+
+    Copyright (c) 2016 Klemens Morgenstern <klemens.morgenstern@ed-chemnitz.de> and
+                       Wenzel Jakob <wenzel.jakob@epfl.ch>
+
+    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"
+
+NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
+
+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 <eval_mode mode = eval_expr>
+object eval(str expr, object global = globals(), object local = object()) {
+    if (!local)
+        local = 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<object>(result);
+}
+
+template <eval_mode mode = eval_expr, size_t N>
+object eval(const char (&s)[N], object global = globals(), object local = object()) {
+    /* Support raw string literals by removing common leading whitespace */
+    auto expr = (s[0] == '\n') ? str(module::import("textwrap").attr("dedent")(s))
+                               : str(s);
+    return eval<mode>(expr, global, local);
+}
+
+inline void exec(str expr, object global = globals(), object local = object()) {
+    eval<eval_statements>(expr, global, local);
+}
+
+template <size_t N>
+void exec(const char (&s)[N], object global = globals(), object local = object()) {
+    eval<eval_statements>(s, global, local);
+}
+
+template <eval_mode mode = eval_statements>
+object eval_file(str fname, object global = globals(), object local = object()) {
+    if (!local)
+        local = global;
+
+    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");
+    }
+
+    int closeFile = 1;
+    std::string fname_str = (std::string) fname;
+#if PY_VERSION_HEX >= 0x03040000
+    FILE *f = _Py_fopen_obj(fname.ptr(), "r");
+#elif PY_VERSION_HEX >= 0x03000000
+    FILE *f = _Py_fopen(fname.ptr(), "r");
+#else
+    /* No unicode support in open() :( */
+    auto fobj = reinterpret_steal<object>(PyFile_FromString(
+        const_cast<char *>(fname_str.c_str()),
+        const_cast<char*>("r")));
+    FILE *f = nullptr;
+    if (fobj)
+        f = PyFile_AsFile(fobj.ptr());
+    closeFile = 0;
+#endif
+    if (!f) {
+        PyErr_Clear();
+        pybind11_fail("File \"" + fname_str + "\" could not be opened!");
+    }
+
+#if PY_VERSION_HEX < 0x03000000 && defined(PYPY_VERSION)
+    PyObject *result = PyRun_File(f, fname_str.c_str(), start, global.ptr(),
+                                  local.ptr());
+    (void) closeFile;
+#else
+    PyObject *result = PyRun_FileEx(f, fname_str.c_str(), start, global.ptr(),
+                                    local.ptr(), closeFile);
+#endif
+
+    if (!result)
+        throw error_already_set();
+    return reinterpret_steal<object>(result);
+}
+
+NAMESPACE_END(PYBIND11_NAMESPACE)