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How to handle Objective-C protocols that contain properties?
...
@interface MyClass () // Class extension
@property (nonatomic, strong) NSString *name;
@end
How to use property in protocol
So to use MyClass with that name property, we have to do either
Declare the property again (AppDelegate.h does this way)
@interface MyClass : NSObject <MyProtocol&...
SQLite add Primary Key
...(i.e. sqlite_autoindex_XXX_1, where XXX is the table name) and set the sql string to NULL. At last change the table definition itself.
One pittfal: sqlite does not see the index name change until the database is reopened. This seems like a bug, but not a severe one (even without reopening the databa...
Calling closure assigned to object property directly
...t;__invoke();
Of course that won't work if the callback is an array or a string (which can also be valid callbacks in PHP) - just for closures and other objects with __invoke behavior.
share
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imp...
Access object child properties using a dot notation string [duplicate]
... scenario that you could put the entire array variable you're after into a string you could use the eval() function.
var r = { a:1, b: {b1:11, b2: 99}};
var s = "r.b.b2";
alert(eval(s)); // 99
I can feel people reeling in horror
...
Redirect stdout to a file in Python?
... to replace the 'w' attribute with, os.O_WRONLY|os.O_CREATE ... can't send strings into the "os" commands!
– Ch'marr
Jul 26 '12 at 21:52
3
...
When vectors are allocated, do they use memory on the heap or the stack?
... // Can't be on stack - how would the stack "expand"
// to make the extra space required between main and foo?
vec.push_back(Type());
}
int main() {
vector<Type> bar;
foo(bar);
}
Likewise:
vector<Type> *vect = new vector<Type>; //allocates vect on hea...
iPhone - Grand Central Dispatch main thread
...rocessing has finished e.g.
- (void)doCalculation
{
//you can use any string instead "com.mycompany.myqueue"
dispatch_queue_t backgroundQueue = dispatch_queue_create("com.mycompany.myqueue", 0);
dispatch_async(backgroundQueue, ^{
int result = <some really long calculation th...
What exactly does += do in python?
... # empty list
x += "something" # iterates over the string and appends to list
print(x) # ['s', 'o', 'm', 'e', 't', 'h', 'i', 'n', 'g']
versus
x=[] # empty list
x = x + "something" # TypeError: can only concatenate list (not "str") to list...
How to include JavaScript file or library in Chrome console?
...message: VM1929:11 Uncaught (in promise) EvalError: Refused to evaluate a string as JavaScript because 'unsafe-eval' is not an allowed source of script in the following Content Security Policy directive: "script-src 'self' blob: filesystem: chrome-extension-resource:".
– Vassi...
“Too many values to unpack” Exception
...no Borini, I am getting also similar error but in my case, I am creating a string as obj='{"vendorId": "' + vID +'", "vendorName" :"'+vName+'", "addedDate" : "'+vAddedDate+'","usersList" : "'+ usersList + '," status" : "'+str(vStatus)+'","edit"'+edit+'"}'; although all the values are string, it give...