Tutorial by Examples: ha

Prior to C++17, when writing a template non-type parameter, you had to specify its type first. So a common pattern became writing something like: template <class T, T N> struct integral_constant { using type = T; static constexpr T value = N; }; using five = integral_constant&l...

Types used in Sets and Dictionaries(key) must conform to Hashable protocol which inherits from Equatable protocol. Custom type conforming to Hashable protocol must implement A calculated property hashValue Define one of the equality operators i.e. == or !=. Following example implements Hasha...

When we want to change root password in windows, We need to follow following steps : Step 1 : Start your Command Prompt by using any of below method : Perss Crtl+R or Goto Start Menu > Run and then type cmd and hit enter Step 2 : Change your directory to where MYSQL is installed, In my case i...

If your application doesn't need to update resources during a specific configuration change and you have a performance limitation that requires you to avoid the activity restart, then you can declare that your activity handles the configuration change itself, which prevents the system from restartin...

Making an app adaptive – that is, responding to size class changes by changing your layout – often involves lots of help from the Auto Layout system. One of the primary ways apps become adaptive is by updating the active Auto Layout constraints when a view's size class changes. For example, conside...

Character literals are a special type of integer literals that are used to represent one character. They are enclosed in single quotes, e.g. 'a' and have the type int. The value of the literal is an integer value according to the machine's character set. They do not allow suffixes. The L prefix bef...

Mockito provides a Matcher<T> interface along with an abstract ArgumentMatcher<T> class to verify arguments. It uses a different approach to the same use-case than the ArgumentCaptor. Additionally the ArgumentMatcher can be used in mocking too. Both use-cases make use of the Mockito.argT...

The following output equivalent results: class IfElseExample { public string DebugToString(object a) { if (a is StringBuilder) { return DebugToStringInternal(a as StringBuilder); } else if (a is List<string>) { ...

HAVING clause removes groups that do not satisfy condition: SELECT type, count(*) as c FROM sys.objects GROUP BY type HAVING count(*) < 10 typecSQ3PK1U5

BackAndroid.addEventListener('hardwareBackPress', function() { if (!this.onMainScreen()) { this.goBack(); return true; } return false; }); Note: this.onMainScreen() and this.goBack() are not built in functions, you also need to implement those. (https://github.c...

To help you find and count characters in a string, CharMatcher provides the following methods: int indexIn(CharSequence sequence) Returns the index of the first character that matches the CharMatcher instance. Returns -­1 if no character matches. int indexIn(CharSequence sequence, int sta...

A StringBuilder represents a series of characters, which unlike a normal string, are mutable. Often times there is a need to modify strings that we've already made, but the standard string object is not mutable. This means that each time a string is modified, a new string object needs to be created,...

Short circuiting is a functionality that skips evaluating parts of a (if/while/...) condition when able. In case of a logical operation on two operands, the first operand is evaluated (to true or false) and if there is a verdict (i.e first operand is false when using &&, first operand is tr...

RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_URI} !(.*)/$ RewriteRule ^(.*)$ /$1/ [L,R=301] The first RewriteCond helps exclude the files. The second RewriteCond checks if there is already a trailing slash. If the case is so RewriteRule is not applied. If you have any URL that s...

Notice, this is only for angular-cli up to 1.0.0-beta.10 version ! Some libraries or plugins may not have typings. Without these, TypeScript can't type check them and therefore causes compilation errors. These libraries can still be used but differently than imported modules. Include a scr...

Shade is a library developed by OpenStack to simplify interactions with OpenStack clouds, like DreamHost. $ pip install shade

Create a file named launch-server.yaml, that will be our playbook. The first part of the playbook is a list of hosts that your playbook will run on, we only have one, localhost. - hosts: localhost Then we need to define a list of tasks to perform in this playbook. We will only have one that lau...

In Sinatra, routing is how your app responds to requests, by the path of the request (e.g. /welcome) and by the HTTP verb used (e.g. GET or POST). The way a request is written is as follows: <http-verb> <path> do <code block to execute when this route is requested> end He...

GetHashCode has major performance effects on Dictionary<> and HashTable. Good GetHashCode Methods should have an even distribution every integer should have a roughly equal chance of returning for a random instance if your method returns the same integer (e.g. the constant '999') for e...

"alpha" is used to specify the opacity for an image. set alpha using XML attribute: android:alpha="0.5" Note: takes float value from 0 (transparent) to 1 (fully visible) set alpha programmatically: imgExample.setAlpha(0.5f);