Tutorial by Examples: u

The option -v followed by an assignment of the form variable=value can be used to pass parameters to an awk program. This is illustrated by the punishment program below, whose job is to write count times the sentence “I shall not talk in class.” on standard output. The following example uses the v...

// Returns the nth number in the Fibonacci sequence function fibonacci(n) { if (n === 1 || n === 0) { return 1; } else { return fibonacci(n - 1) + fibonacci(n - 2); } }

// Checks a string to see if it is a palindrome bool function IsPalindrome(string input) { if (input.size() <= 1) { return true; } else if (input[0] == input[input.size() - 1]) { return IsPalindrome(input.substr(1,input.size() - 2)); } else { r...

Custom events usually need custom event arguments containing information about the event. For example MouseEventArgs which is used by mouse events like MouseDown or MouseUp events, contains information about Location or Buttons which used to generate the event. When creating new events, to create a...

If you have a list, and you want to use the elements of that list as the arguments to a function, what you want is apply: > (apply string-append (list "hello" " " "and hi" " " "are both words")) "hello and hi are both words" > (app...

Functions in Racket can be created with the lambda form. The form takes a list of arguments and a body. (lambda (x y) (* x y)) In the example above, the function takes in two arguments and returns the result of multiplying them. > ((lambda (x y) (* x y)) 4 4) 16 > ((lambda (x y) (* x y)...

Download and install Visual Studio Community 2015 Open Visual Studio Community Click File -> New -> Project Click Templates -> Visual C++ -> Win32 Console Application and then name the project MyFirstProgram. Click Ok Click Next in the following window. Check the Empty proj...

Thread.sleep causes the current thread to suspend execution for a specified period. This is an efficient means of making processor time available to the other threads of an application or other applications that might be running on a computer system. There are two overloaded sleep methods in the Thr...

To set a value in NSUserDefaults, you can use the following functions: Swift < 3 setBool(_:forKey:) setFloat(_:forKey:) setInteger(_:forKey:) setObject(_:forKey:) setDouble(_:forKey:) setURL(_:forKey:) Swift 3 In Swift 3 the names of function is changed to set insted of set folloed by ...

To get a value in NSUserDefaults you can use the following functions: Swift arrayForKey(_:) boolForKey(_:) dataForKey(_:) dictionaryForKey(_:) floatForKey(_:) integerForKey(_:) objectForKey(_:) stringArrayForKey(_:) stringForKey(_:) doubleForKey(_:) URLForKey(_:) Objective-C -(nullab...

REM This is a comment REM is the official comment command.

::This is a label that acts as a comment The double-colon :: comment shown above is not documented as being a comment command, but it is a special case of a label that acts as a comment. Caution: when labels are used as comments within a bracketed code block or for command, the command processor...

It is also possible to use variables as comments. This can be useful to conditionally prevent commands being executed: @echo off setlocal if /i "%~1"=="update" (set _skip=) Else (set _skip=REM) %_skip% copy update.dat %_skip% echo Update applied ... When using the ab...

There are use cases when you might want to rename your app directory to something else. In Laravel4 you could just change a config entry, here's one way to do it in Laravel5. In this example we'll be renaming the app directory to src. Override Application class The directories name app is hardcod...

The function angular.isFunction determines and returns true if and only if the value passed to is a reference to a function. The function returns a reference to the now extended destination object angular.isFunction(fn) Examples var onClick = function(e) {return e}; angular.isFunction(onCli...

The function angular.toJson will take an object and serialize it into a JSON formatted string. Unlike the native function JSON.stringify, This function will remove all properties beginning with $$ (as angular usually prefixes internal properties with $$) angular.toJson(object) As data needs to ...

The function angular.fromJson will deserialize a valid JSON string and return an Object or an Array. angular.fromJson(string|object) Note that this function is not limited to only strings, it will output a representation of any object passed to it. Examples: angular.fromJson("{\"yo...

Environment variables can be defined before the meteor call, like so: PORT=4000 meteor NODE_ENV="staging" meteor

In javascript, assigning a non-primitive value (Such as Object, Array, Function, and many more), keeps a reference (an address in the memory) to the assigned value. Assigning a primitive value (String, Number, Boolean, or Symbol) to two different variables, and changing one, won't change both: var...

Be careful, this approach might be considered as a bad design for angular apps, since it requires programmers to remember both where functions are placed in the scope tree, and to be aware of scope inheritance. In many cases it would be preferred to inject a service (Angular practice - using scope ...