newint.py 文件源码

def __new__(cls, x=0, base=10):
        """
        From the Py3 int docstring:

        |  int(x=0) -> integer
        |  int(x, base=10) -> integer
        |
        |  Convert a number or string to an integer, or return 0 if no
        |  arguments are given.  If x is a number, return x.__int__().  For
        |  floating point numbers, this truncates towards zero.
        |
        |  If x is not a number or if base is given, then x must be a string,
        |  bytes, or bytearray instance representing an integer literal in the
        |  given base.  The literal can be preceded by '+' or '-' and be
        |  surrounded by whitespace.  The base defaults to 10.  Valid bases are
        |  0 and 2-36. Base 0 means to interpret the base from the string as an
        |  integer literal.
        |  >>> int('0b100', base=0)
        |  4

        """
        try:
            val = x.__int__()
        except AttributeError:
            val = x
        else:
            if not isint(val):
                raise TypeError('__int__ returned non-int ({0})'.format(
                    type(val)))

        if base != 10:
            # Explicit base
            if not (istext(val) or isbytes(val) or isinstance(val, bytearray)):
                raise TypeError(
                    "int() can't convert non-string with explicit base")
            try:
                return super(newint, cls).__new__(cls, val, base)
            except TypeError:
                return super(newint, cls).__new__(cls, newbytes(val), base)
        # After here, base is 10
        try:
            return super(newint, cls).__new__(cls, val)
        except TypeError:
            # Py2 long doesn't handle bytearray input with an explicit base, so
            # handle this here.
            # Py3: int(bytearray(b'10'), 2) == 2
            # Py2: int(bytearray(b'10'), 2) == 2 raises TypeError
            # Py2: long(bytearray(b'10'), 2) == 2 raises TypeError
            try:
                return super(newint, cls).__new__(cls, newbytes(val))
            except:
                raise TypeError("newint argument must be a string or a number,"
                                "not '{0}'".format(type(val)))