Tutorial by Examples: od

This exception occurs when a collection is modified while iterating over it using methods other than those provided by the iterator object. For example, we have a list of hats and we want to remove all those that have ear flaps: List<IHat> hats = new ArrayList<>(); hats.add(new Ushanka...

pip is your friend when you need to install any package from the plethora of choices available at the python package index (PyPI). pip is already installed if you're using Python 2 >= 2.7.9 or Python 3 >= 3.4 downloaded from python.org. For computers running Linux or another *nix with a native...

There are two possible ways to pass a value type by reference: ref and out. The difference is that by passing it with ref the value must be initialized but not when passing it with out. Using out ensures that the variable has a value after the method call: public void ByRef(ref int value) { C...

Of the LINQ methods which use deferred execution, some require a single value to be evaluated at a time. The following code: var lst = new List<int>() {3, 5, 1, 2}; var streamingQuery = lst.Select(x => { Console.WriteLine(x); return x; }); foreach (var i in streamingQuery) { ...

If you don't have permissions to install perl modules, you may still install them manually, indicating a custom path where you've got writing permissions. Fist, download and unzip module archive: wget module.tar.gz tar -xzf module.tar.gz cd module Then, if the module distribution contains a M...

Error handling is important but can make an elegant algorithm into a mess. Railway Oriented Programming (ROP) is used to make error handling elegant and composable. Consider the simple function f: let tryParse s = let b, v = System.Int32.TryParse s if b then Some v else None let f (g : ...

MATCH (n) WHERE n.some_attribute = "some identifier" SET n.other_attribute = "a new value"

The attribute status_code contains the status code of the response good_req = requests.get('https://api.github.com/events') code_200 = good_req.status_code notfound_req = requests.get('https://api.github.com/not_found') code_404 = notfound_req.status_code requests.codes.__dict__ will provid...

In Visual Studio go to your Solution Explorer then click on Project you will be adding model Right mouse. Choose ADO.NET Entity Data Model Then choose Generate from database and click Next in next window click New Connection... and point to the database you want to generate model from (Could be M...

Encoding //convert the image to NSData first let imageData:NSData = UIImagePNGRepresentation(image)! // convert the NSData to base64 encoding let strBase64:String = imageData.base64EncodedStringWithOptions(.Encoding64CharacterLineLength) Decoding let dataDecoded:NSData = NSData(base64Encoded...

In Insert mode, press <C-r> and then % to insert the filename. This technique is applicable to all registers. For e.g. if in insert mode, you want to paste the current search pattern, you can type <C-r> and then /.

In the node JS command prompt, inside your loopback project, type the following command to create a new model. slc loopback:model If you have installed LoopBack CLI tool, you can create model with: lb model The command prompt will request informations about the model to create. In this examp...

You can use the following code for going back and forward. if (!function_exists('codepoint_encode')) { function codepoint_encode($str) { return substr(json_encode($str), 1, -1); } } if (!function_exists('codepoint_decode')) { function codepoint_decode($str) { re...

You can use the following code for going back and forward. if (!function_exists('mb_internal_encoding')) { function mb_internal_encoding($encoding = NULL) { return ($from_encoding === NULL) ? iconv_get_encoding() : iconv_set_encoding($encoding); } } if (!function_exists('mb_c...

C and C++ are well known as high-performance languages - largely due to the heavy amount of code customization, allowing a user to specify performance by choice of structure. When optimizing it is important to benchmark relevant code and completely understand how the code will be used. Common opti...

The most straightforward approach to optimizing is by executing less code. This approach usually gives a fixed speed-up without changing the time complexity of the code. Even though this approach gives you a clear speedup, this will only give noticable improvements when the code is called a lot. R...

As Rebar3 is free, open source and written in Erlang, it's possible to simply clone and build it from the source code. $ git clone https://github.com/erlang/rebar3.git $ cd rebar3 $ ./bootstrap This will create the rebar3 script, which you can put on your PATH or link to /usr/local/bin as expl...

String#to_time Converts a string to a Time value. The form parameter can be either :utc or :local, defaults to :local. "13-12-2012".to_time # => 2012-12-13 00:00:00 +0100 "06:12".to_time # => 2012-12-13 06:12:00 +0100 "2012-12-13 06...

const foobar = `foo bar` encoding := base64.StdEncoding encodedFooBar := make([]byte, encoding.EncodedLen(len(foobar))) encoding.Encode(encodedFooBar, []byte(foobar)) fmt.Printf("%s", encodedFooBar) // Output: Zm9vIGJhcg== Playground

str := base64.StdEncoding.EncodeToString([]byte(`foo bar`)) fmt.Println(str) // Output: Zm9vIGJhcg== Playground