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Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
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If during the evaluation of an expression, the result is not mathematically defined or not in the range of
representable values for its type, the behavior is undefined. [ Note: most existing implementations of C++
ignore integer overflows. Treatment of division by zero, forming a remainde...
What is managed or unmanaged code in programming?
..., CLR, the foundation of the .net framework, IL, CLI execution environment etc etc
– BKSpurgeon
Mar 3 '16 at 1:32
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Django filter queryset __in for *every* item in list
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Summary:
One option is, as suggested by jpic and sgallen in the comments, to add .filter() for each category. Each additional filter adds more joins, which should not be a problem for small set of categories.
There is the aggregation approach. This query would be shorter and...
How to remove all of the data in a table using Django
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Inside a manager:
def delete_everything(self):
Reporter.objects.all().delete()
def drop_table(self):
cursor = connection.cursor()
table_name = self.model._meta.db_table
sql = "DROP TABLE %s;" % (table_name, )
cursor.execute(sql)
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Evaluating a mathematical expression in a string
...p://pyparsing.wikispaces.com/message/view/home/15549426
'''
__note__ = '''
All I've done is rewrap Paul McGuire's fourFn.py as a class, so I can use it
more easily in other places.
'''
class NumericStringParser(object):
'''
Most of this code comes from the fourFn.py pyparsing example
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What platforms have something other than 8-bit char?
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Control Data mainframes (CDC-6400, 6500, 6600, 7600, Cyber 170, Cyber 176 etc.) 6-bit chars, packed 10 per 60-bit word.
Unisys mainframes: 9 bits/byte
Windows CE: simply doesn't support the `char` type at all -- requires 16-bit wchar_t instead
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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not initialized.
From PHP documentation:
No warning is generated if the variable does not exist. T...
What's the difference between a Python module and a Python package?
...stem in the reference documentation: It’s important to keep in mind that all packages are modules.
– Martijn Pieters♦
Apr 23 '18 at 21:42
7
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Everyauth vs Passport.js?
...ty of authentication mechanisms, including OpenID, OAuth, BrowserID, SAML, etc.
Flexible
Passport is just middleware, using the fn(req, res, next) convention established by Connect and Express.
This means that there are no surprises, as you define where you want your routes and when you want to u...
How to specify in crontab by what user to run script? [closed]
...e that this method won't work with crontab -e, but only works if you edit /etc/crontab directly. Otherwise, you may get an error like /bin/sh: www-data: command not found
Just before the program name:
*/1 * * * * www-data php5 /var/www/web/includes/crontab/queue_process.php >> /var/www/web/i...