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This is a simple but robust core-data set-up for iOS 10+. There are exactly two way to access core-data: viewContext. The viewContext can only be used from the main thread, and only for reading. strong enqueueCoreDataBlock. All writing should be done using enqueueCoreDataBlock. There is no ne...

lazy var persistentContainer: NSPersistentContainer = { let container = NSPersistentContainer(name: "ProjectName") container.loadPersistentStores(completionHandler: { (storeDescription, error) in if let error = error { fatalError("Unreso...

Just some methods of an object can be mocked using spy() of mockito. For example, imagine that method class requires some web service to work. public class UserManager { List<User> users; public UserManager() { user = new LinkedLisk<User>(); } ...

Get the Source Package from http://typo3.org/download/ and upload this package to your web server. Put it one level above the document root. For this manual, we will use the .tar.gz file. Use the shell to execute the according commands: /var/www/site/htdocs/$ cd .. /var/www/site/$ wget get.typo3....

go() method The go() method loads a specific URL from the history list. The parameter can either be a number which goes to the URL within the specific position (-1 goes back one page, 1 goes forward one page), or a string. The string must be a partial or full URL, and the function will go to the f...

The spacing should be even and uniform throughout. Improper indentation can cause an IndentationError or cause the program to do something unexpected. The following example raises an IndentationError: a = 7 if a > 5: print "foo" else: print "bar" print "done&qu...

The following example shows a basic main GUI window with a label widget, a toolbar, and a status bar using PyQt4. import sys from PyQt4 import QtGui class App(QtGui.QApplication): def __init__(self, sys_argv): super(App, self).__init__(sys_argv) self.build_ui() ...

This basic code will launch a "Hello world" GUI window using PyQt4: import sys from PyQt4 import QtGui # create instance of QApplication app = QtGui.QApplication(sys.argv) # create QLabel, without parent it will be shown as window label = QtGui.QLabel('Hello world!') label.show(...

hashlib.new requires the name of an algorithm when you call it to produce a generator. To find out what algorithms are available in the current Python interpreter, use hashlib.algorithms_available: import hashlib hashlib.algorithms_available # ==> {'sha256', 'DSA-SHA', 'SHA512', 'SHA224', 'dsa...

The PBKDF2 algorithm exposed by hashlib module can be used to perform secure password hashing. While this algorithm cannot prevent brute-force attacks in order to recover the original password from the stored hash, it makes such attacks very expensive. import hashlib import os salt = os.urandom...

This method looks for the existence of browser specific things. This would be more difficult to spoof, but is not guaranteed to be future proof. // Opera 8.0+ var isOpera = (!!window.opr && !!opr.addons) || !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0; // Firefox 1.0+ ...

An easier approach for some would be to use an existing JavaScript library. This is because it can be tricky to guarantee browser detection is correct, so it can make sense to use a working solution if one is available. One popular browser-detection library is Bowser. Usage example: if (bowser.ms...

This method gets the user agent and parses it to find the browser. The browser name and version are extracted from the user agent through a regex. Based on these two, the <browser name> <version> is returned. The four conditional blocks following the user agent matching code are meant t...

Let's add a custom operator to multiply a CGSize func *(lhs: CGFloat, rhs: CGSize) -> CGSize{ let height = lhs*rhs.height let width = lhs*rhs.width return CGSize(width: width, height: height) } Now this works let sizeA = CGSize(height:100, width:200) let sizeB = 1.1 * si...

When we have two separate array and we want to make key value pair from that two array, we can use array's reduce function like below: var columns = ["Date", "Number", "Size", "Location", "Age"]; var rows = ["2001", "5", "B...

When you are copying a string into a malloced buffer, always remember to add 1 to strlen. char *dest = malloc(strlen(src)); /* WRONG */ char *dest = malloc(strlen(src) + 1); /* RIGHT */ strcpy(dest, src); This is because strlen does not include the trailing \0 in the length. If you take the ...

A programming best practice is to free any memory that has been allocated directly by your own code, or implicitly by calling an internal or external function, such as a library API like strdup(). Failing to free memory can introduce a memory leak, which could accumulate into a substantial amount of...

char buf[8]; /* tiny buffer, easy to overflow */ printf("What is your name?\n"); scanf("%s", buf); /* WRONG */ scanf("%7s", buf); /* RIGHT */ If the user enters a string longer than 7 characters (- 1 for the null terminator), memory behind the buffer buf will be...

If realloc fails, it returns NULL. If you assign the value of the original buffer to realloc's return value, and if it returns NULL, then the original buffer (the old pointer) is lost, resulting in a memory leak. The solution is to copy into a temporary pointer, and if that temporary is not NULL, th...

Detailed instructions on getting asp.net-mvc-4 set up or installed.