From 5ec6fdb0f6ffe467ed0cfc630354129fc6bad319 Mon Sep 17 00:00:00 2001 From: Georg Brandl Date: Sat, 17 Mar 2012 17:25:47 +0100 Subject: Closes #14342: remove out-of-date section about avoiding recursion errors. --- Doc/library/re.rst | 22 ---------------------- 1 file changed, 22 deletions(-) diff --git a/Doc/library/re.rst b/Doc/library/re.rst index 5a14408..8744bdb 100644 --- a/Doc/library/re.rst +++ b/Doc/library/re.rst @@ -1090,28 +1090,6 @@ The equivalent regular expression would be :: (\S+) - (\d+) errors, (\d+) warnings -Avoiding recursion -^^^^^^^^^^^^^^^^^^ - -If you create regular expressions that require the engine to perform a lot of -recursion, you may encounter a :exc:`RuntimeError` exception with the message -``maximum recursion limit exceeded``. For example, :: - - >>> s = 'Begin ' + 1000*'a very long string ' + 'end' - >>> re.match('Begin (\w| )*? end', s).end() - Traceback (most recent call last): - File "", line 1, in ? - File "/usr/local/lib/python3.2/re.py", line 132, in match - return _compile(pattern, flags).match(string) - RuntimeError: maximum recursion limit exceeded - -You can often restructure your regular expression to avoid recursion. - -Simple uses of the ``*?`` pattern are special-cased to avoid recursion. Thus, -the above regular expression can avoid recursion by being recast as ``Begin -[a-zA-Z0-9_ ]*?end``. As a further benefit, such regular expressions will run -faster than their recursive equivalents. - .. _search-vs-match: search() vs. match() -- cgit v0.12 From 557a3ec9bbf875abaea6b4c1bed577405182db63 Mon Sep 17 00:00:00 2001 From: Georg Brandl Date: Sat, 17 Mar 2012 17:26:27 +0100 Subject: Closes #14343: avoid shadowing builtin input() in example code. --- Doc/library/re.rst | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/Doc/library/re.rst b/Doc/library/re.rst index 8744bdb..0e4acd8 100644 --- a/Doc/library/re.rst +++ b/Doc/library/re.rst @@ -1136,7 +1136,7 @@ creates a phonebook. First, here is the input. Normally it may come from a file, here we are using triple-quoted string syntax: - >>> input = """Ross McFluff: 834.345.1254 155 Elm Street + >>> text = """Ross McFluff: 834.345.1254 155 Elm Street ... ... Ronald Heathmore: 892.345.3428 436 Finley Avenue ... Frank Burger: 925.541.7625 662 South Dogwood Way @@ -1150,7 +1150,7 @@ into a list with each nonempty line having its own entry: .. doctest:: :options: +NORMALIZE_WHITESPACE - >>> entries = re.split("\n+", input) + >>> entries = re.split("\n+", text) >>> entries ['Ross McFluff: 834.345.1254 155 Elm Street', 'Ronald Heathmore: 892.345.3428 436 Finley Avenue', -- cgit v0.12