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performSelector may cause a leak because its selector is unknown
...s for a reason. It's very rare that this warning should simply be ignored, and it's easy to work around. Here's how:
if (!_controller) { return; }
SEL selector = NSSelectorFromString(@"someMethod");
IMP imp = [_controller methodForSelector:selector];
void (*func)(id, SEL) = (void *)imp;
func(_contr...
How do I create a constant in Python?
...ng on other people's work, I have added an answer, far below, with a short and simple implementation of "Constants" for python 2.7 (which lacks "enum"). These are enum-like read-only name.attribute, and can contain any value. Declaration is easy Nums = Constants(ONE=1, PI=3.14159, DefaultWidth=100.0...
How do I read / convert an InputStream into a String in Java?
...ou have a java.io.InputStream object, how should you process that object and produce a String ?
59 Answers
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Why does sizeof(x++) not increment x?
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From the C99 Standard (the emphasis is mine)
6.5.3.4/2
The sizeof operator yields the size (in bytes) of its operand, which may be an expression or the parenthesized name of a type. The size is determined from the type of the opera...
Can I split an already split hunk with git?
I've recently discovered git's patch option to the add command, and I must say it really is a fantastic feature.
I also discovered that a large hunk could be split into smaller hunks by hitting the s key, which adds to the precision of the commit.
But what if I want even more precision, if the...
How to exit if a command failed?
I am a noob in shell-scripting. I want to print a message and exit my script if a command fails. I've tried:
8 Answers
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How to create dictionary and add key–value pairs dynamically?
...Basically, you're creating an object literal with 2 properties (called key and value) and inserting it (using push()) into the array.
Edit: So almost 5 years later, this answer is getting downvotes because it's not creating an "normal" JS object literal (aka map, aka hash, aka dictionary).
It is ...
Unable to find specific subclass of NSManagedObject
...r Xcode 7 (final):
Prepending the module name to the class (as in Xcode 6 and early beta releases of Xcode 7) is no longer necessary.
The Apple documentation Implementing Core Data Managed Object Subclasses has been
updated accordingly.
The Data Model inspector
has now two fields "Class" and "Mod...
What is the difference between '/' and '//' when used for division?
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In Python 3.x, 5 / 2 will return 2.5 and 5 // 2 will return 2. The former is floating point division, and the latter is floor division, sometimes also called integer division.
In Python 2.2 or later in the 2.x line, there is no difference for integers unless y...
Should I make HTML Anchors with 'name' or 'id'?
...cation, 5.9.8 Navigating to a fragment identifier:
For HTML documents (and the text/html MIME type), the following processing model must be followed to determine what the indicated part of the document is.
Parse the URL, and let fragid be the <fragment> component of the URL.
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