Modules/future_builtins.c

/* future_builtins module */

/* This module provides functions that will be builtins in Python 3.0,
   but that conflict with builtins that already exist in Python
   2.x. */


#include "Python.h"

PyDoc_STRVAR(module_doc,
"This module provides functions that will be builtins in Python 3.0,\n\
but that conflict with builtins that already exist in Python 2.x.\n\
\n\
Functions:\n\
\n\
ascii(arg) -- Returns the canonical string representation of an object.\n\
filter(pred, iterable) -- Returns an iterator yielding those items of \n\
       iterable for which pred(item) is true.\n\
hex(arg) -- Returns the hexadecimal representation of an integer.\n\
map(func, *iterables) -- Returns an iterator that computes the function \n\
    using arguments from each of the iterables.\n\
oct(arg) -- Returns the octal representation of an integer.\n\
zip(iter1 [,iter2 [...]]) -- Returns a zip object whose .next() method \n\
    returns a tuple where the i-th element comes from the i-th iterable \n\
    argument.\n\
\n\
The typical usage of this module is to replace existing builtins in a\n\
module's namespace:\n \n\
from future_builtins import ascii, filter, map, hex, oct, zip\n");

static PyObject *
builtin_hex(PyObject *self, PyObject *v)
{
    return PyNumber_ToBase(v, 16);
}

PyDoc_STRVAR(hex_doc,
"hex(number) -> string\n\
\n\
Return the hexadecimal representation of an integer or long integer.");


static PyObject *
builtin_oct(PyObject *self, PyObject *v)
{
    return PyNumber_ToBase(v, 8);
}

PyDoc_STRVAR(oct_doc,
"oct(number) -> string\n\
\n\
Return the octal representation of an integer or long integer.");


static PyObject *
builtin_ascii(PyObject *self, PyObject *v)
{
    return PyObject_Repr(v);
}

PyDoc_STRVAR(ascii_doc,
"ascii(object) -> string\n\
\n\
Return the same as repr().  In Python 3.x, the repr() result will\n\
contain printable characters unescaped, while the ascii() result\n\
will have such characters backslash-escaped.");

/* List of functions exported by this module */

static PyMethodDef module_functions[] = {
    {"hex",             builtin_hex,        METH_O, hex_doc},
    {"oct",             builtin_oct,        METH_O, oct_doc},
    {"ascii",           builtin_ascii,      METH_O, ascii_doc},
    {NULL,              NULL}   /* Sentinel */
};


/* Initialize this module. */

PyMODINIT_FUNC
initfuture_builtins(void)
{
    PyObject *m, *itertools, *iter_func;
    char *it_funcs[] = {"imap", "ifilter", "izip", NULL};
    char **cur_func;

    m = Py_InitModule3("future_builtins", module_functions, module_doc);
    if (m == NULL)
        return;

    itertools = PyImport_ImportModuleNoBlock("itertools");
    if (itertools == NULL)
        return;

    /* If anything in the following loop fails, we fall through. */
    for (cur_func = it_funcs; *cur_func; ++cur_func){
        iter_func = PyObject_GetAttrString(itertools, *cur_func);
        if (iter_func == NULL ||
            PyModule_AddObject(m, *cur_func+1, iter_func) < 0)
            break;
    }
    Py_DECREF(itertools);
    /* any other initialization needed */
}