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Objective-C: Property / instance variable in category
...ey;
@implementation MyClass
- (NSString *)test {
NSString *result = objc_getAssociatedObject(self, &MyClassResultKey);
if (result == nil) {
// do a lot of stuff
result = ...;
objc_setAssociatedObject(self, &MyClassResultKey, result, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
...
Why is string concatenation faster than array join?
...tenation:
// ECMA-262, section 15.5.4.6
function StringConcat() {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined", ["String.prototype.concat"]);
}
var len = %_ArgumentsLength();
var this_as_string = TO_STRING_INLINE(t...
How to step back in Eclipse debugger?
... Matt McHenryMatt McHenry
17.7k77 gold badges6060 silver badges6262 bronze badges
...
PostgreSQL: insert from another table
...
Just supply literal values in the SELECT:
INSERT INTO TABLE1 (id, col_1, col_2, col_3)
SELECT id, 'data1', 'data2', 'data3'
FROM TABLE2
WHERE col_a = 'something';
A select list can contain any value expression:
But the expressions in the select list do not have to reference any columns i...
Site stopped working in asp.net System.Web.WebPages.Razor.Configuration.HostSection cannot be cast t
...he context
'Default' at location
'C:\Windows\Microsoft.Net\assembly\GAC_MSIL\System.Web.WebPages.Razor\v4.0_2.0.0.0__31bf3856ad364e35\System.Web.WebPages.Razor.dll'.
Type B originates from 'System.Web.WebPages.Razor, Version=3.0.0.0,
Culture=neutral, PublicKeyToken=31bf3856ad364e35' in the c...
Instance variables vs. class variables in Python
...test:
import timeit
setup='''
XGLOBAL= 5
class A:
xclass = 5
def __init__(self):
self.xinstance = 5
def f1(self):
xlocal = 5
x = self.xinstance
def f2(self):
xlocal = 5
x = A.xclass
def f3(self):
xlocal = 5
x = XGLOBAL
...
add created_at and updated_at fields to mongoose schemas
Is there a way to add created_at and updated_at fields to a mongoose schema, without having to pass them in everytime new MyModel() is called?
...
Git: updating remote branch information
... James Wald
13k55 gold badges4747 silver badges6060 bronze badges
answered Oct 22 '10 at 7:00
Jakub NarębskiJakub Narębski
2...
What's the valid way to include an image with no src?
...
– user56reinstatemonica8
Aug 28 '13 at 15:06
4
You might want to think twice about inlining your resour...
Explanation of strong and weak storage in iOS5
...lse". It's the "someone else" that is important.
Consider the following:
__strong id strongObject = <some_object>;
__weak id weakObject = strongObject;
Now we've got a two pointers to <some_object>, one strong and one weak. If we set strongObject to nil like so:
strongObject = nil;
...