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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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How to remove all of the data in a table using Django
...
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)
...
SASS - use variables across multiple files
I would like to keep one central .scss file that stores all SASS variable definitions for a project.
6 Answers
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Can't pickle when using multiprocessing Pool.map()
...nsider it "easy" or not;-) is to add the infrastructure to your program to allow such methods to be pickled, registering it with the copy_reg standard library method.
For example, Steven Bethard's contribution to this thread (towards the end of the thread) shows one perfectly workable approach to a...
Get class that defined method
...ited Jun 20 '14 at 19:44
Aaron Hall♦
260k6969 gold badges353353 silver badges303303 bronze badges
answered Jun 7 '09 at 2:23
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Best way to structure a tkinter application? [closed]
The following is the overall structure of my typical python tkinter program.
7 Answers
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How do I check OS with a preprocessor directive?
...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 defined; checking for either should work.
Linux
__linux__
linux Obsolete (not POSIX compliant)
__linux Obsolete (not POSIX compliant)
...
how to delete all cookies of my website in php
I'm wondering if I can delete all my website's cookies when a user click on logout, because I used this as function to delete cookies but it isn't work properly:
...
How to install Boost on Ubuntu
I'm on Ubuntu, and I want to install Boost. I tried with
7 Answers
7
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