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How do I implement an Objective-C singleton that is compatible with ARC?
...;
return sharedInstance;
}
else,you should do this:
+ (id)allocWithZone:(NSZone *)zone
{
static MyClass *sharedInstance = nil;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
sharedInstance = [super allocWithZone:zone];
});
return sharedInstance;...
What does Expression.Quote() do that Expression.Constant() can’t already do?
...resentation for two very different things is extremely confusing and bug prone.
Long answer:
Consider the following:
(int s)=>(int t)=>s+t
The outer lambda is a factory for adders that are bound to the outer lambda's parameter.
Now, suppose we wish to represent this as an expression tre...
HTML 5 Favicon - Support?
...80 pixels as that is the current size recommend by Apple for the latest iPhones and iPads. I have read Blackberry will also use rel="apple-touch-icon-precomposed".
As a note: Chrome for Android states:
The apple-touch-* are deprecated, and will be supported only for a short time. (Written as o...
Set selected radio from radio group with a value
...you first need to remove checked attribute from any of radio buttons under one radio buttons group only then you will be able to add checked property / attribute to one of the radio button in that radio buttons group.
Code To Remove Checked Attribute from all radio buttons of one radio button group...
Picking a random element from a set
...ts, i.e., structures that have a .get() function.
– coneyhelixlake
Feb 19 '15 at 22:27
4
@bourbak...
How to run a program without an operating system?
...rogram that is on the drive)?
General answer to the question: it can be done.
It's often referred to as "bare metal programming".
To read from flash drive, you want to know what's USB, and you want to have some driver to work with this USB. The program on this drive would also have to be in some p...
How do you merge two Git repositories?
...
Or read Eric Lee's "Merging Two Git Repositories Into One Repository Without Losing File History" saintgimp.org/2013/01/22/…
– Jifeng Zhang
Oct 8 '13 at 12:17
...
Is there a benefit to defining a class inside another class in Python?
...
You might want to do this when the "inner" class is a one-off, which will never be used outside the definition of the outer class. For example to use a metaclass, it's sometimes handy to do
class Foo(object):
class __metaclass__(type):
....
instead of defining a ...
EF Migrations: Rollback last applied migration?
...le migrations
PM> Update-Database -TargetMigration:"CategoryIdIsLong"
One solution would be to create a wrapper PS script that automates the steps above. Additionally, feel free to create a feature request for this, or better yet, take a shot at implementing it! https://github.com/dotnet/ef6
...
How to read a single character from the user?
Is there a way of reading one single character from the user input? For instance, they press one key at the terminal and it is returned (sort of like getch() ). I know there's a function in Windows for it, but I'd like something that is cross-platform.
...