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Being able to read non-python text files is not a purpose of linecache, but it does work and people use it. This changeset adjusts the language to make it clear that Python files are not treated uniquely, but does not go so far as to say reading non-python files is explicitly supported.
55 lines
2 KiB
ReStructuredText
55 lines
2 KiB
ReStructuredText
:mod:`linecache` --- Random access to text lines
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================================================
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.. module:: linecache
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:synopsis: This module provides random access to individual lines from text files.
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.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
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**Source code:** :source:`Lib/linecache.py`
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--------------
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The :mod:`linecache` module allows one to get any line from a Python source file, while
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attempting to optimize internally, using a cache, the common case where many
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lines are read from a single file. This is used by the :mod:`traceback` module
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to retrieve source lines for inclusion in the formatted traceback.
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The :func:`tokenize.open` function is used to open files. This
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function uses :func:`tokenize.detect_encoding` to get the encoding of the
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file; in the absence of an encoding token, the file encoding defaults to UTF-8.
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The :mod:`linecache` module defines the following functions:
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.. function:: getline(filename, lineno, module_globals=None)
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Get line *lineno* from file named *filename*. This function will never raise an
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exception --- it will return ``''`` on errors (the terminating newline character
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will be included for lines that are found).
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.. index:: triple: module; search; path
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If a file named *filename* is not found, the function will look for it in the
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module search path, ``sys.path``, after first checking for a :pep:`302`
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``__loader__`` in *module_globals*, in case the module was imported from a
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zipfile or other non-filesystem import source.
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.. function:: clearcache()
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Clear the cache. Use this function if you no longer need lines from files
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previously read using :func:`getline`.
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.. function:: checkcache(filename=None)
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Check the cache for validity. Use this function if files in the cache may have
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changed on disk, and you require the updated version. If *filename* is omitted,
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it will check all the entries in the cache.
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Example::
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>>> import linecache
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>>> linecache.getline(linecache.__file__, 8)
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'import sys\n'
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