Tutorial by Examples: n

A lexer action is a block of arbitrary code in the target language surrounded by {...}, which is executed during matching: IDENTIFIER: [A-Z]+ { log("matched rule"); }; A semantic predicate is a block of arbitrary code in the target language surrounded by {...}?, which evaluates to a bo...

if we want to change the Controllers directory we need: Move and/or rename the default Controllers directory where we want it. For example from app/Http/Controllers to app/Controllers Update all the namespaces of the files inside the Controllers folder, making they adhere to the new path, re...

There are several ways to insert data: Using the DB Facade public function run() { DB::table('users') ->insert([ 'name' => 'Taylor', 'age' => 21 ]); } Via Instantiating a Model public function run() { $user = new User; $us...

Within your DatabaseSeeder class you are able to call other seeders $this->call(TestSeeder::class) This allows you to keep one file where you can easily find your seeders. Keep in mind that you need to pay attention to the order of your calls regarding foreign key constraints. You can't refe...

Functions within a class can be overloaded for when they are accessed through a cv-qualified reference to that class; this is most commonly used to overload for const, but can be used to overload for volatile and const volatile, too. This is because all non-static member functions take this as a hi...

# make this routine available outside this translation unit .globl string_to_integer string_to_integer: # function prologue push %ebp mov %esp, %ebp push %esi # initialize result (%eax) to zero xor %eax, %eax # fetch pointer to the string mov 8(%ebp), %e...

Disclaimer: the examples presented here are only for the purpose of showing the use of abstract classes and inheritance and may not necessarily be of a practical use. Also, there is no sich thing as polymorphic in MATLAB and therefore the use of abstract classes is limited. This example is to show w...

A class or a structure may declare any function it's friend. If a function is a friend of a class, it may access all it's protected and private members: // Forward declaration of functions. void friend_function(); void non_friend_function(); class PrivateHolder { public: PrivateHolder(in...

Methods may declared as friends as well as functions: class Accesser { public: void private_accesser(); }; class PrivateHolder { public: PrivateHolder(int val) : private_value(val) {} friend void Accesser::private_accesser(); private: int private_value; }; void Access...

A whole class may be declared as friend. Friend class declaration means that any member of the friend may access private and protected members of the declaring class: class Accesser { public: void private_accesser1(); void private_accesser2(); }; class PrivateHolder { public: P...

In every applications life-cycle comes a day where it's components needs to be updated. Everyone knows the pain of updating every single dependency one-by-one. Well here you just need to issue the command: npm update (-g) If the "-g" is there then npm will update the global packages. ...

This is a protected and non-static method of the Object class. This method is used to perform some final operations or clean up operations on an object before it gets removed from the memory. According to the doc, this method gets called by the garbage collector on an object when garbage collecti...

Fast and short way to extract extension from file name in JavaScript will be: function get_extension(filename) { return filename.slice((filename.lastIndexOf('.') - 1 >>> 0) + 2); } It works correctly both with names having no extension (e.g. myfile) or starting with . dot (e.g. .h...

Fast and short way to format value of type Number as money, e.g. 1234567.89 => "1,234,567.89": var num = 1234567.89, formatted; formatted = num.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,'); // "1,234,567.89" More advanced variant with support of any number o...

function assign(obj, prop, value) { if (typeof prop === 'string') prop = prop.split('.'); if (prop.length > 1) { var e = prop.shift(); assign(obj[e] = Object.prototype.toString.call(obj[e]) === '[object Object]' ? obj[e] ...

Here is an example of how to import a function that is defined in an unmanaged C++ DLL. In the C++ source code for "myDLL.dll", the function add is defined: extern "C" __declspec(dllexport) int __stdcall add(int a, int b) { return a + b; } Then it can be included into ...

""" ================================================================================ CREATE A 2 BY 2 GRID OF SUB-PLOTS WITHIN THE SAME FIGURE. ================================================================================ """ import matplotlib.pyplot as plt ...

""" ================================================================================ DRAW MULTIPLE LINES IN THE SAME PLOT ================================================================================ """ import matplotlib.pyplot as plt ...

JavaFX 8 The following example demonstrates how to add custom properties that can be styled from css to a custom Node. Here 2 DoublePropertys are added to the Rectangle class to allow setting the width and height from CSS. The following CSS could be used for styling the custom node: StyleableRe...

Objective-C supports a special type called `instancetype that can only be used as type returned by a method. It evaluates to the class of the receiving object. Consider the following class hierarchy: @interface Foo : NSObject - (instancetype)initWithString:(NSString *)string; @end @interf...