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The following method computes the value of num raised to the power of exp using recursion: public long power(final int num, final int exp) { if (exp == 0) { return 1; } if (exp == 1) { return num; } return num * power(num, exp - 1); } This illustrates ...

Meteor has it's own package repository on atmospherejs.com You can add new packages from atmosphere by running: meteor add [package-author-name:package-name] For example: meteor add kadira:flow-router Similarly, you can remove the same package by: meteor remove kadira:flow-router To see...

$ man -w find /usr/share/man/man1/find.1.gz $ man -w printf /usr/share/man/man1/printf.1.gz $ man -w man /usr/share/man/man1/man.1.gz

The ng-show directive shows or hides the HTML element based on if the expression passed to it is true or false. If the value of the expression is falsy then it will hide. If it is truthy then it will show. The ng-hide directive is similar. However, if the value is falsy it will show the HTML elemen...

Install jquery via npm : npm install jquery --save Install typings for the library: To add typings for a library, do the following: typings install jquery --global --save Add jquery to angular-cli-build.js file to vendorNpmFiles array: This is required so the build system...

You can search for man pages containing a particular string in their description using: man -k <string> For example: man -k unzip Might return: man -k unzip IO::Uncompress::Bunzip2(3pm) - Read bzip2 files/buffers IO::Uncompress::Gunzip(3pm) - Read RFC 1952 files/buffers IO::Uncom...

Create an interface decorated with a ServiceContract attribute and member functions decorated with the OperationContract attribute. namespace Service { [ServiceContract] interface IExample { [OperationContract] string Echo(string s); } } Create a concrete...

$(window).load() was deprecated in jQuery version 1.8 (and completely removed from jQuery 3.0) and as such should not be used anymore. The reasons for the deprecation are noted on the jQuery page about this event Caveats of the load event when used with images A common challenge developers attem...

There are two kinds of boolean operators in Elixir: boolean operators (they expect either true or false as their first argument) x or y # true if x is true, otherwise y x and y # false if x is false, otherwise y not x # false if x is true, otherwise true All of booleans...

An explicit intent is used for starting an activity or service within the same application package. In this case the name of the intended class is explicitly mentioned: Intent intent = new Intent(this, MyComponent.class); startActivity(intent); However, an implicit intent is sent across the sys...

Attach an Event Handler Since version 1.7 jQuery has the event API .on(). This way any standard javascript event or custom event can be bound on the currently selected jQuery element. There are shortcuts such as .click(), but .on() gives you more options. HTML <button id="foo">b...

Sometimes what you want to do is just too complex for a filter or a simple_tag. Fow this you will need to create a compilation function and a renderer. In this example we will create a template tag verbose_name with the following syntax: ExampleDescription{% verbose_name obj %}Verbose name of a mo...

var_dump(filter_var(true, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE)); // true var_dump(filter_var(false, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE)); // false var_dump(filter_var(1, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE)); // true var_dump(filter_var(0, FILTER_VALIDATE_BOOL...

Validates value as float, and converts to float on success. var_dump(filter_var(1, FILTER_VALIDATE_FLOAT)); var_dump(filter_var(1.0, FILTER_VALIDATE_FLOAT)); var_dump(filter_var(1.0000, FILTER_VALIDATE_FLOAT)); var_dump(filter_var(1.00001, FILTER_VALIDATE_FLOAT)); var_dump(filter_var('1', FILTE...

Remove all characters except letters, digits and !#$%&'*+-=?^_`{|}~@.[]. var_dump(filter_var('[email protected]', FILTER_SANITIZE_EMAIL)); var_dump(filter_var("!#$%&'*+-=?^_`{|}~.[]@example.com", FILTER_SANITIZE_EMAIL)); var_dump(filter_var('john/@example.com', FILTER_SANITIZE_EM...

Remove all characters except digits, plus and minus sign. var_dump(filter_var(1, FILTER_SANITIZE_NUMBER_INT)); var_dump(filter_var(-1, FILTER_SANITIZE_NUMBER_INT)); var_dump(filter_var(+1, FILTER_SANITIZE_NUMBER_INT)); var_dump(filter_var(1.00, FILTER_SANITIZE_NUMBER_INT)); var_dump(filter_var(...

Sanitze URLs Remove all characters except letters, digits and $-_.+!*'(),{}|\^~[]`<>#%";/?:@&= var_dump(filter_var('http://www.example.com/path/to/dir/index.php?test=y', FILTER_SANITIZE_URL)); var_dump(filter_var("http://www.example.com/path/to/dir/index.php?test=y!#$%&'*+...

If IPython (or Jupyter) are installed, the debugger can be invoked using: import ipdb ipdb.set_trace() When reached, the code will exit and print: /home/usr/ook.py(3)<module>() 1 import ipdb 2 ipdb.set_trace() ----> 3 print("Hello world!") ipdb> Clea...

There may be situations where you have setup a pool of MySQL connections, but you have a number of queries you would like to run in sequence: SELECT 1; SELECT 2; You could just run then using pool.query as seen elsewhere, however if you only have one free connection in the pool you must wait un...

You can attach the query executed to your err object when an error occurs: var q = mysql.query('SELECT `name` FROM `pokedex` WHERE `id` = ?', [ 25 ], function (err, result) { if (err) { // Table 'test.pokedex' doesn't exist err.query = q.sql; // SELECT `name` FROM `pokedex` WHERE `id` ...