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In this question, @Viclib asked about using rewrite rules to exploit typeclass laws to eliminate some overloaded function calls: Mind the following class: class ListIsomorphic l where toList :: l a -> [a] fromList :: [a] -> l a I also demand that toList . fromList == id. H...

Here are some example on how to add new filters/functions to twig,the synax for adding Twig_Functions are the same as the Twig_Filter ones, just change the keywords accordingly <?php $twig = new Twig_Environment($loader); /* You can chain a global function */ $twig->addFilter(ne...

Here is a workaround to temporary reset your password for your account. Login to your hosting panel and use the database tool that is available (probably PHPmyAdmin). Load the appropriate database and then go to the jos_users table. (The database prefix might be different for your case). ...

A defer statement consists of a block of code, which will be executed when a function returns and should be used for cleanup. As Swift's guard statements encourage a style of early return, many possible paths for a return may exist. A defer statement provides cleanup code, which then does not need ...

When using a defer-statement, make sure the code remains readable and the execution order remains clear. For example, the following use of the defer-statement makes the execution order and the function of the code hard to comprehend. postfix func ++ (inout value: Int) -> Int { defer { value...

Django supports MySQL 5.5 and higher. Make sure to have some packages installed: $ sudo apt-get install mysql-server libmysqlclient-dev $ sudo apt-get install python-dev python-pip # for python 2 $ sudo apt-get install python3-dev python3-pip # for python 3 As well as ...

When write() is called for a named or unnamed pipe or stream socket whose reading end is closed, two things happen: POSIX.1-2001 SIGPIPE signal is sent to the process that called write() POSIX.1-2004 SIGPIPE signal is sent to the thread that called write() EPIPE error is returned ...

function onButtonClick() { navigator.bluetooth.requestDevice({filters: [{services: ['battery_service']}]}) .then(device => { // Connecting to GATT Server... return device.gatt.connect(); }) .then(server => { // Getting Battery Service... return server.getPri...

A Threadpool has a Queue of tasks, of which each will be executed on one these Threads. The following example shows how to add two int arrays using a Threadpool. Java SE 8 int[] firstArray = { 2, 4, 6, 8 }; int[] secondArray = { 1, 3, 5, 7 }; int[] result = { 0, 0, 0, 0 }; ExecutorService po...

While you can use the NSUserDefaults methods anywhere, it can sometimes be better to define a manager that saves and reads from NSUserDefaults for you and then use that manager for reading or writing your data. Suppose that we want to save a user’s score into NSUserDefaults. We can create a class ...

NSLog(@"%s %d %s, yourVariable: %@", __FILE__, __LINE__, __PRETTY_FUNCTION__, yourVariable); Will log the file, line number and function data along with any variables you want to log. This can make the log lines much longer, particularly with verbose file and method names, however it ca...

Given a Day, we can perform simple arithmetic and comparisons, such as adding: import Data.Time addDays 1 (fromGregorian 2000 1 1) -- 2000-01-02 addDays 1 (fromGregorian 2000 12 31) -- 2001-01-01 Subtract: addDays (-1) (fromGregorian 2000 1 1) -- 1999-12-31 addDays (-1) (fromGregorian...

function footag_func( $atts ) { return "foo = {$atts['foo']}"; } add_shortcode( 'footag', 'footag_func' ); In plugins we can add shortcodes using the add_shortcode function. The shortcode can be used in any Wordpress page or post just by enclosing it in square brackets. [footag...

Code snippet: import java.util.Set; public class ThreadStatus { public static void main(String args[]) throws Exception { for (int i = 0; i < 5; i++){ Thread t = new Thread(new MyThread()); t.setName("MyThread:" + i); t.start(); ...

x = np.random.random([100,100]) x.tofile('/path/to/dir/saved_binary.npy') y = fromfile('/path/to/dir/saved_binary.npy') z = y.reshape(100,100) all(x==z) # Output: # True

The function np.loadtxt can be used to read csv-like files: # File: # # Col_1 Col_2 # 1, 1 # 2, 4 # 3, 9 np.loadtxt('/path/to/dir/csvlike.txt', delimiter=',', comments='#') # Output: # array([[ 1., 1.], # [ 2., 4.], # [ 3., 9.]]) The same file could be read ...

(Caveat emptor: there are many, many programmers who go into absolute conniptions if they meet code that uses recordsets instead of commands and stored procedures.) <% dim rs, sql dim SelectedUser SelectedUser = request.form("user") if IsNumeric(SelectedUser) then SelectedUser...

To add shadows to text, use the text-shadow property. The syntax is as follows: text-shadow: horizontal-offset vertical-offset blur color; Shadow without blur radius h1 { text-shadow: 2px 2px #0000FF; } This creates a blue shadow effect around a heading Shadow with blur radius To add a...

You can do a permissions check when sending an Intent to a registered broadcast receiver. The permissions you send are cross-checked with the ones registered under the tag. They restrict who can send broadcasts to the associated receiver. To send a broadcast request with permissions, specify the p...

ActionMailer also allows attaching files. attachments['filename.jpg'] = File.read('/path/to/filename.jpg') By default, attachments will be encoded with Base64. To change this, you can add a hash to the attachments method. attachments['filename.jpg'] = { mime_type: 'application/gzip', enco...