Tutorial by Examples: e

A lambda can only have a trailing return type; the leading return type syntax is not applicable to lambdas. Note that in many cases it is not necessary to specify a return type for a lambda at all. struct Base {}; struct Derived1 : Base {}; struct Derived2 : Base {}; auto lambda = [](bool b) -&g...

Iterators utilize a form of the for loop known as the generic for loop. The generic form of the for loop uses three parameters: An iterator function that gets called when the next value is needed. It receives both the invariant state and control variable as parameters. Returning nil signals term...

The Lua standard library provides two iterator functions that can be used with a for loop to traverse key-value pairs within tables. To iterate over a sequence table we can use the library function ipairs. for index, value in ipairs {'a', 'b', 'c', 'd', 'e'} do print(index, value) --> 1 a, ...

Both pairs and ipairs represent stateless iterators. A stateless iterator uses only the generic for loop's control variable and invariant state to compute the iteration value. Pairs Iterator We can implement the stateless pairs iterator using the next function. -- generator function which initial...

Stateful iterators carry some additional information about the current state of the iterator. Using Tables The addition state can be packed into the generic for loop's invariant state. local function chars_iter(t, i) local i = i + 1 if i <= t.len then return i, t.s:sub(i, i)...

The C programming language allows multidimensional arrays. Here is the general form of a multidimensional array declaration − type name[size1][size2]...[sizeN]; For example, the following declaration creates a three dimensional (5 x 10 x 4) integer array: int arr[5][10][4]; Two-dimensional A...

Step by Step Guide :- Step 1 :- Set constraint to UIView Leading. 2) Top. 3) Trailing. (From mainview) Step 2 :- Set constrain to Label 1 Leading 2) Top 3) Trailing (From it's superview) Step 3 :- Set constraint to Label 2 Leading 2) Top 3) Trailing (From its superview) Step...

Python 2.x2.7 In Python 2, if you want to define a class boolean value by yourself, you need to implement the __nonzero__ method on your class. The value is True by default. class MyClass: def __nonzero__(self): return False my_instance = MyClass() print bool(MyClass) # Tru...

import pandas as pd generate random DF df = pd.DataFrame(np.random.randint(0,10,size=(10, 3)), columns=list('ABC')) In [16]: print(df) A B C 0 4 1 4 1 0 2 0 2 7 8 8 3 2 1 9 4 7 3 8 5 4 0 7 6 1 5 5 7 6 7 8 8 6 7 3 9 6 4 5 select rows where value...

Example A var i,a,b,len; a = {x:0,y:0} function test(){ // return object created each call return {x:0,y:0}; } function test1(a){ // return object supplied a.x=0; a.y=0; return a; } for(i = 0; i < 100; i ++){ // Loop A b = test(); } for(i = 0; i < 100; ...

Without a try catch block, undefined functions will throw errors and stop execution: undefinedFunction("This will not get executed"); console.log("I will never run because of the uncaught error!"); Will throw an error and not run the second line: // Uncaught ReferenceError:...

Think of the mediator pattern as the flight control tower that controls planes in the air: it directs this plane to land now, the second to wait, and the third to take off, etc. However no plane is ever allowed to talk to its peers. This is how mediator works, it works as a communication hub among ...

It is also possible to pass your custom object to other activities using the Bundle class. There are two ways: Serializable interface—for Java and Android Parcelable interface—memory efficient, only for Android (recommended) Parcelable Parcelable processing is much faster than serializable....

.Rprofile is a file containing R code that is executed when you launch R from the directory containing the .Rprofile file. The similarly named Rprofile.site, located in R's home directory, is executed by default every time you load R from any directory. Rprofile.site and to a greater extend .Rprofil...

Yii2 provides efficient ways to retrieve data from the database.Consider an example of a simple employee table having fields emp_id, emp_name and emp_salary. In order to retrieve the employee names and their salaries, we use the query. select emp_name,emp_salary from employee To generate the abo...

Multiple conditions can be written using where() method as given below. // Creates a new \yii\db\Query() object $query = new \yii\db\Query(); $rows = $query->select(['emp_name','emp_salary']) ->from('employee') ->where(['emp_name' => 'Kiran', 'emp_salary' => 2500...

This example intend to be a gentle introduction to the Excel Object Model for beginners. Open the Visual Basic Editor (VBE) Click View --> Immediate Window to open the Immediate Window (or ctrl + G): You should see the following Immediate Window at the bottom on VBE: This wi...

gradlew tasks -- show all tasks Android tasks ------------- androidDependencies - Displays the Android dependencies of the project. signingReport - Displays the signing info for each variant. sourceSets - Prints out all the source sets defined in this project. Build tasks -----------...

Suppose we have a JSON string： ["first","second","third"] We can parse this JSON string into a String array : Gson gson = new Gson(); String jsonArray = "[\"first\",\"second\",\"third\"]"; String[] strings = gson.fromJson(j...

For this example to work you'll need a JDBC driver compatible to the system the database is running on. An opensource one that allows you to connect to DB2 databases on an IBM System i can be found here: JT400 Even though this example is DB2 specific, it works for almost every other system if you e...