If we want to commit only part of changes of the same file

--patch

or

-p

is used

git add --patch

Similar to the above command

git add -p

Possible answers for the command:

y

stage this hunk for the next commit

n

do not stage this hunk for the next commit

q

quit; do not stage this hunk or any of the remaining hunks

a

stage this hunk and all later hunks in the file

d

do not stage this hunk or any of the later hunks in the file ... The complete list of the possible answers is on the link of the note

Built-in built-in higher order functions that expect to receive a function as an argument

document.addEventListener('click', func);
function func() {
    alert('You clicked me!');
}

Using anonymous function:

document.addEventListener('click', function() {
    alert('You clicked me!');
});

Another built-in function

foreach

that receives a function as an argument

let greatColors = ['green', 'orange', 'yellow'];

greatColors.forEach(listColors);

function listColors(color) {
    document.write('The color ' + color + ' is a great color<br>');
}

XML

stands for

Extensible Markup Language

application/xml

is the official Internet media type for XML.

.xml

is the XML filename extension.

XML is extensible

− XML allows us to create our own self-descriptive tags.

XML carries the data, does not present it

− XML allows us to store the data irrespective of how it will be presented.

XML is a public standard

- XML was developed by an organization called the World Wide Web Consortium. Any type of data can be expressed as an

XML document

XML can be used to

exchange

the information between companies and systems

An XML file contains XML-elements, also called XML-nodes or XML-tags

<?xml version="1.0" encoding = "UTF-8"?>
<student>
   <name>George</name>
   <city>Tbilisi</city>
   <phone>(011) 123-4567</phone>
</student>

The names of XML-elements are enclosed by triangular brackets

< >

<element>

Each XML-element

needs to be closed

either with start or with end elements as shown below

<element>...</element>

XML allows self-closing elements, for example if the tag empty

<?xml version="1.0"?>
<student>
   <name>George</name>
   <city>Tbilisi</city>
   <address/>
   <phone>(011) 123-4567</phone>
</student>

Children elements must not overlap parent elements. i.e., an element end tag must follow all of its children's end tags.

<company>

is closed after the

</contact-info>

tag but it's opened after

</contact-info>

tag, which is wrong!

<?xml version = "1.0"?>
<contact-info>
<company>Learn Practice Teach
</contact-info>
</company>

The following example shows the correct nested tags

<?xml version = "1.0"?>
<contact-info>
   <company>Applications.ge</company>
<contact-info>

One

root element

is necessary for an XML document. In this example below, both

<x>

and

<y>

elements are at the top level and they don't have one parent element, which is wrong:

<?xml version = "1.0"?>
<x>...</x>
<y>...</y>

XML-elements are

case-sensitive

, which means that the start and the end elements names need to be exactly in the same case. This example is not correct XML document, because

case sensitivity

is not correctly applied

<?xml version="1.0"?>
<student>
   <name>George</name>
   <city>Tbilisi</city>
   <address/>
   <phone>(011) 123-4567</Phone>
</student>

In this case

<phone>

and its close tag

</phone>

is not in the same case

a { background-color: yellow; }

a

- selector

{

- declaration start

background-color

- property

:

- property/value separator

yellow

- value

;

- declaration separator

}

- declaration end

1. Interface supports multiple inheritance

class Class_A { }
class Class_B { }
abstract class MyAbstractClass extends Class_A, Class_B { }

Parse error:  syntax error, unexpected ',', expecting '{' in...

. 2. Interface contains only incomplete member (contains only signature of a method)

interface Animal {
    function run() {
        echo 'I am running!';
    }
}

Fatal error:  Interface function Animal::run() cannot contain body in ...

. 3. Interface does not contain data member

interface MyInterface {
    public $foo = null;
}

Fatal error:  Interfaces may not include member variables in ...

. 4. Interface can not have access modifiers (other than

public

), by default everything is assumed as public

interface iTemplate
{
    private function setVariable($name, $var);
    public function getHtml($template);
}

Fatal error:  Access type for interface method iTemplate::setVariable() must be omitted in ...

. Notes (mistakes on the page): 1. Interface does contain CONSTRUCTOR (but can force child classes to implement constructor) as well as abstract class can contain one

interface MyInterface {
    function __construct();
}
class mathh implements MyInterface {
    // function __construct(){ }
}

2. We can have static methods inside interface as well as inside abstract classes

interface MyInterface {
    static function getPI();
}
class mathh implements MyInterface {
    static function getPI(){
        return 3.1415926535;
    }
}

3. Abstract class can contain abstract static member

abstract class Animal {
    // child classes must implement this
    abstract static function prey();

    static public function run() {
        echo "I am running!\n";
    }
}
class Dog extends Animal {
    static public function prey() {
        echo "I killed the cat !\n";
    }
}
$dog = new Dog();
$dog->prey(); // I killed the cat !

XML declaration example

<?xml version = "1.0" encoding = "UTF-8" standalone = "yes"?>

XML document can optionally have an XML declaration. XML document without declaration is also valid

<student>
   <name>George</name>
   <city>Tbilisi</city>
   <phone>(011) 123-4567</phone>
</student>

If the XML declaration is included, it must contain version number attribute

<?xml encoding="UTF-8" standalone="no"?>
<student>
   <name>George</name>
   <city>Tbilisi</city>
   <phone>(011) 123-4567</phone>
</student>

It will generate the following error:

error on line 1 at column 7: Malformed declaration expecting version

The names are always in lower case

<?xml Version="1.0" encoding="UTF-8" standalone="no"?>
<student>
   <name>George</name>
   <city>Tbilisi</city>
   <phone>(011) 123-4567</phone>
</student>

It will generate the following error:

error on line 1 at column 7: Malformed declaration expecting version

The XML declaration must begin with

<?xml

<? version="1.0" encoding="UTF-8" standalone="no"?>
<student>
   <name>George</name>
   <city>Tbilisi</city>
   <phone>(011) 123-4567</phone>
</student>

The following error will be generated:

error on line 1 at column 3: xmlParsePI : no target name

If document contains XML declaration, it must be the

first statement

<student>
   <name>George</name>
   <city>Tbilisi</city>
   <phone>(011) 123-4567</phone>
</student>
<?xml version="1.0" encoding="UTF-8" standalone="no"?>

The error will be the following:

error on line 6 at column 6: XML declaration allowed only at the start of the document

The order of placing the parameters is important. The correct order is:

version

,

encoding

and

standalone

<?xml encoding="UTF-8" standalone="no" version="1.0"?>
<student>
   <name>George</name>
   <city>Tbilisi</city>
   <phone>(011) 123-4567</phone>
</student>

This will generate the following error:

error on line 1 at column 7: Malformed declaration expecting version

Either single or double quotes may be used. Here is valid XML document

<?xml version='1.0' encoding='UTF-8' standalone="no"?>
<student>
   <name>George</name>
   <city>Tbilisi</city>
   <phone>(011) 123-4567</phone>
</student>

An HTTP protocol can override the value of encoding that we put in the declaration.

Creates several multiplier functions without using

Higher order function

function doubleMe(number) {
    return 2*number;
}
function tripleMe(number) {
    return 3*number;
}
function quadrupleMe(number) {
    return 4*number;
}
document.write(doubleMe(10));
document.write(tripleMe(10));
document.write(quadrupleMe(10));

Creates the same multiplier functions using

Higher order function

In this case we only need to create one function instead of 3 multiplier functions

function multiplier(multiply) {
    return function(number){
        return number*multiply;
    };
}

let double = multiplier(2);
let triple = multiplier(3);
let quadruple = multiplier(4);

document.write(double(10));
document.write(triple(10));
document.write(quadruple(10));

First we add

click

event listener for two functions:

func1

,

func2

to document object. After clicking three times we remove the event listener for

func1

function

let counter = 0;
document.addEventListener('click', func1);
document.addEventListener('click', func2);

function func1(){
    console.log('You clicked me!');
  
    if (counter>2) {
        console.log('Max limit is 3');
        document.removeEventListener('click', func1);
    }
}
function func2(){
    counter ++;
    console.log('counter: '+counter);
}

.accordion {
  max-width: 600px;

  &__copy {
    display: none;
    padding: 1rem 1.5rem 2rem 1.5rem;

    &--open {
      display: block;
    }
  }
}

This will generate the following regular CSS:

.accordion {
  max-width: 600px;
}
.accordion__copy {
  display: none;
  padding: 1rem 1.5rem 2rem 1.5rem;
}
.accordion__copy--open {
  display: block;
}