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What is the difference between a weak reference and an unowned reference?
...a.k.a. they don't increase the retain count in order to prevent ARC from deallocating the referred object).
But why two keywords? This distinction has to do with the fact that Optional types are built-in the Swift language. Long story short about them: optional types offer memory safety (this works ...
What is the most efficient way to deep clone an object in JavaScript?
...
Native deep cloning
It's called "structured cloning", works experimentally in Node 11 and later, and hopefully will land in browsers. See this answer for more details.
Fast cloning with data loss - JSON.parse/stringify
If you do not use Dates, funct...
How do I use installed packages in PyCharm?
...you use the os (ex. apt-get), or pip in a virtualenv, packages will be installed to a location already on the path.
In your example, GNU Radio is installed to the system Python 2's standard site-packages location, which is already in the path. Pointing PyCharm at the correct interpreter is enough;...
Clean code to printf size_t in C++ (or: Nearest equivalent of C99's %z in C++)
...isual C++ for instance use %Iu and %Id respectively, I think that gcc will allow you to use %zu and %zd.
You could create a macro:
#if defined(_MSC_VER) || defined(__MINGW32__) //__MINGW32__ should goes before __GNUC__
#define JL_SIZE_T_SPECIFIER "%Iu"
#define JL_SSIZE_T_SPECIFIER "%Id"
...
Getting All Variables In Scope
Is there a way to get all variables that are currently in scope in javascript?
10 Answers
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What does the PHP error message “Notice: Use of undefined constant” mean?
...l_escape_string($_POST['message']);
As is, it was looking for constants called department, name, email, message, etc. When it doesn't find such a constant, PHP (bizarrely) interprets it as a string ('department', etc). Obviously, this can easily break if you do defined such a constant later (tho...
How to customize the background/border colors of a grouped table view cell?
...later UITableViewCell now has a backgroundColor property that makes this really easy (especially in combination with the [UIColor colorWithPatternImage:] initializer). But I'll leave the 2.0 version of the answer here for anyone that needs it…
It's harder than it really should be. Here's how I ...
Working with Enums in android
...lmost done with a calculation activity I am working with in android for my app. I try to create a Gender Enum, but for some reason getting Syntax error, insert "EnumBody" to complete EnumDeclaration.
...
Adding external library into Qt Creator project
... this is like this:
LIBS += -L/path/to -lpsapi
This way it will work on all platforms supported by Qt. The idea is that you have to separate the directory from the library name (without the extension and without any 'lib' prefix). Of course, if you are including a Windows specific lib, this reall...
enum - getting value of enum on string conversion
...>> member.value
1
You could add a __str__ method to your enum, if all you wanted was to provide a custom string representation:
class D(Enum):
def __str__(self):
return str(self.value)
x = 1
y = 2
Demo:
>>> from enum import Enum
>>> class D(Enum):
...