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Assignment in an if statement
I have a class Animal , and its subclass Dog .
I often find myself coding the following lines:
17 Answers
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RuntimeException: Unable to instantiate application
...-install .apk file and trying to reuse or recycle the previous opened activity/view from the same package (if you haven't closed the previous installed app yet). It has nothing to do with your app, moreover, it is very unlikely that your app will get freezed or crashed cause by this verbose error me...
vector::at vs. vector::operator[]
I know that at() is slower than [] because of its boundary checking, which is also discussed in similar questions like C++ Vector at/[] operator speed or ::std::vector::at() vs operator[] << surprising results!! 5 to 10 times slower/faster! . I just don't understand what the at() met...
How to create a directory if it doesn't exist using Node.js?
Is this the right way to create a directory if it doesn't exist.
It should have full permission for the script and readable by others.
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Why does NULL = NULL evaluate to false in SQL server
In SQL server if you have nullParam=NULL in a where clause, it always evaluates to false. This is counterintuitive and has caused me many errors. I do understand the IS NULL and IS NOT NULL keywords are the correct way to do it. But why does SQL server behave this way?
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Why not use tables for layout in HTML? [closed]
It seems to be the general opinion that tables should not be used for layout in HTML.
66 Answers
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Using a strategy pattern and a command pattern
Both design patterns encapsulate an algorithm and decouple implementation details from their calling classes. The only difference I can discern is that the Strategy pattern takes in parameters for execution, while the Command pattern doesn't.
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How can I troubleshoot my Perl CGI script?
...is answer is intended as a general framework for working through
problems with Perl CGI scripts and originally appeared on Perlmonks as Troubleshooting Perl CGI Scripts. It is not a complete guide to every
problem that you may encounter, nor a tutorial on bug squashing. It
is just the culmination ...
What are the differences between struct and class in C++?
...ween class and struct is defined in (11.2):
Member of a class defined with the
keyword class are private by
default. Members of a class defined
with the keywords struct or union
are public by default.
Additional difference: the keyword class can be used to declare template parameters, ...
What is the preferred syntax for defining enums in JavaScript?
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Since 1.8.5 it's possible to seal and freeze the object, so define the above as:
const DaysEnum = Object.freeze({"monday":1, "tuesday":2, "wednesday":3, ...})
or
const DaysEnum = {"monday":1, "tuesday":2, "wednesday":3, ...}
Object.free...