40 lines
1.4 KiB
ReStructuredText
40 lines
1.4 KiB
ReStructuredText
:mod:`builtins` --- Built-in objects
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====================================
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.. module:: builtins
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:synopsis: The module that provides the built-in namespace.
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This module provides direct access to all 'built-in' identifiers of Python; for
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example, ``builtins.open`` is the full name for the built-in function
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:func:`open`. See chapter :ref:`builtin`.
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This module is not normally accessed explicitly by most applications, but can be
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useful in modules that provide objects with the same name as a built-in value,
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but in which the built-in of that name is also needed. For example, in a module
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that wants to implement an :func:`open` function that wraps the built-in
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:func:`open`, this module can be used directly::
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import builtins
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def open(path):
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f = builtins.open(path, 'r')
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return UpperCaser(f)
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class UpperCaser:
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'''Wrapper around a file that converts output to upper-case.'''
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def __init__(self, f):
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self._f = f
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def read(self, count=-1):
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return self._f.read(count).upper()
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# ...
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As an implementation detail, most modules have the name ``__builtins__`` made
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available as part of their globals. The value of ``__builtins__`` is normally
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either this module or the value of this modules's :attr:`__dict__` attribute.
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Since this is an implementation detail, it may not be used by alternate
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implementations of Python.
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