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Multi-line string with extra space (preserved indentation)
...o use a helper function and some variable substitution tricks:
unset text
_() { text="${text}${text+
}${*}"; }
# That's an empty line which demonstrates the reasoning behind
# the usage of "+" instead of ":+" in the variable substitution
# above.
_ ""
_ "this is line one"
_ "this is line two"
_ "...
How do I correctly clean up a Python object?
__del__(self) above fails with an AttributeError exception. I understand Python doesn't guarantee the existence of "global variables" (member data in this context?) when __del__() is invoked. If that is the case and this is the reason for the exception, how do I make sure the object destructs...
理解Python的 with 语句 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...hat the statement after with has to evaluate an object that responds to an __enter__() as well as an __exit__() function.
这看起来充满魔法，但不仅仅是魔法，Python对with的处理还很聪明。基本思想是with所求值的对象必须有一个__enter__()方法，一个__exit__()...
How do I check OS with a preprocessor directive?
...ecks. Here are a few of them, with links to where they're found:
Windows
_WIN32 Both 32 bit and 64 bit
_WIN64 64 bit only
Unix (Linux, *BSD, Mac OS X)
See this related question on some of the pitfalls of using this check.
unix
__unix
__unix__
Mac OS X
__APPLE__
__MACH__
Both are de...
what does the __file__ variable mean/do?
...
When a module is loaded from a file in Python, __file__ is set to its path. You can then use that with other functions to find the directory that the file is located in.
Taking your examples one at a time:
A = os.path.join(os.path.dirname(__file__), '..')
# A is the par...
select count(*) from table of mysql in php
...mysql_query("SELECT count(*) as total_count from Students ") or exit(mysql_error());
$row = mysql_fetch_object($num_result);
echo $row->total_count;
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How to define two fields “unique” as couple
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I would say you'll get a "ValidationError" exception. Have a look at the Django docs: Model.validate_unique
– Jens
Apr 10 '10 at 15:09
2
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Print all properties of a Python Class [duplicate]
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vars only works if you are using __dict__ to store the attributes (which is the default behaviour for Python objects). Refer to @BasicWolf's answer if you are using __slots__
– Cyctemic
Feb 20 '14 at 10:23
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Can modules have properties the same way that objects can?
...ance. So, for example, your m.py module file could be:
import sys
class _M(object):
def __init__(self):
self.c = 0
def afunction(self):
self.c += 1
return self.c
y = property(afunction)
sys.modules[__name__] = _M()
...
ReSharper - force curly braces around single line
...oping for was to be able to set up ReSharper to do a yellow warning or red error when the rule was violated, but I haven't found a way to do that. Because you're right, Gorohoroh, Cleanup Code does a lot of stuff and I'd like to have the option to look at and fix the rule violations one at a time.
...