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Why are #ifndef and #define used in C++ header files?
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Those are called #include guards.
Once the header is included, it checks if a unique value (in this case HEADERFILE_H) is defined. Then if it's not defined, it defines it and continues to the rest of the page.
When the code is included again, the first ifndef fails, resulting in a blank...
Is there any difference between “foo is None” and “foo == None”?
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is always returns True if it compares the same object instance
Whereas == is ultimately determined by the __eq__() method
i.e.
>>> class Foo(object):
def __eq__(self, other):
return True
>>> f = Foo()
>>&...
Debugging Package Manager Console Update-Database Seed Method
I wanted to debug the Seed() method in my Entity Framework database configuration class when I run Update-Database from the Package Manager Console but didn't know how to do it. I wanted to share the solution with others in case they have the same issue.
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How to call a Parent Class's method from Child Class in Python?
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Yes, but only with new-style classes. Use the super() function:
class Foo(Bar):
def baz(self, arg):
return super().baz(arg)
For python < 3, use:
class Foo(Bar):
def baz(self, arg):
return super(Foo, self).baz...
Will the base class constructor be automatically called?
Would the age of customer be 2? It seems like the base class's constructor will be called no matter what. If so, why do we need to call base at the end sometimes?
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How do I print the type or class of a variable in Swift?
...the examples below to the new Swift 2.0 syntax (e.g. println was replaced with print, toString() is now String()).
From the Xcode 6.3 release notes:
@nschum points out in the comments that the Xcode 6.3 release notes show another way:
Type values now print as the full demangled type name when ...
Timeout for python requests.get entire response
I'm gathering statistics on a list of websites and I'm using requests for it for simplicity. Here is my code:
19 Answers
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Timeout function if it takes too long to finish [duplicate]
...l script that loops through a text file containing URL:s that I want to visit and take screenshots of.
2 Answers
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How to use underscore.js as a template engine?
...e.js and express framework. Then I saw about underscore.js as a set of utility functions. I saw this question on stackoverflow
. It says we can use underscore.js as a template engine. anybody know good tutorials about how to use underscore.js for templating, especially for biginners who have less ...
How to delete last item in list?
...rogram that calculates the time taken to answer a specific question, and quits out of the while loop when answer is incorrect, but i want to delete the last calculation, so i can call min() and it not be the wrong time, sorry if this is confusing.
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