Tutorial by Examples: s

When tokens like '{' are used in a parser rule, an implicit lexer rule will be created for them unless an explicit rule exists. In other words, if you have a lexer rule: OPEN_BRACE: '{'; Then both of these parser rules are equivalent: parserRule: '{'; parserRule: OPEN_BRACE; But if the OPE...

Several lexer rules can match the same input text. In that case, the token type will be chosen as follows: First, select the lexer rule which matches the longest input If the text matches an implicitly defined token (like '{'), use the implicit rule If several lexer rules match the same input l...

A lexer rule can have associated commands: WHITESPACE: [ \r\n] -> skip; Commands are defined after a -> at the end of the rule. skip: Skips the matched text, no token will be emited channel(n): Emits the token on a different channel type(n): Changes the emitted token type mode(n), pu...

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...

# 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...

>> img = imread('football.jpg'); Use imread to read image files into a matrix in MATLAB. Once you imread an image, it is stored as an ND-array in memory: >> size(img) ans = 256 320 3 The image 'football.jpg' has 256 rows and 320 columns and it has 3 color channels: Red, ...

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. ...

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] ...

""" ================================================================================ 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...

UCanAccess is a pure Java JDBC driver that allows us to read from and write to Access databases without using ODBC. It uses two other packages, Jackcess and HSQLDB, to perform these tasks. Once it has been set up*, we can work with data in .accdb and .mdb files using code like this: import java.sq...