Function features

Август 21, 2022

Содержание

2. AGENDA Arrow functions Default parameters IIFE
3. ARROW FUNCTIONS An arrow function expression is a syntactically compact alternative to a regular function expression
4. ARROW FUNC vs REGULAR FUNC An arrow function has not its own bindings to the: this,
5. COMPACT FORM If we have single line operation in function, we can use short-compact form of
6. DEFAULT PARAMETERS Default function parameters allow named parameters to be initialized with default values if no
7. WHY WE NEED THIS? Function parameters default to undefined. However, it's often useful to set a
8. BEFORE DEFAULT PARAMETERS Examples of expressions that can be converted to false are: null, NaN, 0,
9. IIFE An IIFE (Immediately Invoked Function Expression) is a JavaScript function that runs as soon as
10. SELF-EXECUTING ANONYMOUS FUNCTION It is a design pattern which is also known as a Self-Executing Anonymous
12. Скачать презентацию

Слайд 2

AGENDA
Arrow functions
Default parameters
IIFE

Слайд 3

ARROW FUNCTIONS
An arrow function expression is a syntactically compact alternative to

a regular function expression

Слайд 4

ARROW FUNC vs REGULAR FUNC
An arrow function has not its own

bindings to the:
this,
arguments,
super
Arrow function expressions are ill suited as methods, and they cannot be used as constructors.

Слайд 5

COMPACT FORM
If we have single line operation in function, we can

use short-compact form of arrow function without {} and return

Слайд 6

DEFAULT PARAMETERS
Default function parameters allow named parameters to be initialized with

default values if no value or undefined is passed.

Слайд 7

WHY WE NEED THIS?
Function parameters default to undefined. However, it's often

useful to set a different default value. This is where default parameters can help.

Слайд 8

BEFORE DEFAULT PARAMETERS
Examples of expressions that can be converted to false

are:
null,
NaN,
0,
empty string ("" or '' or ``),
undefined.

|| (OR) operator can be used with operands that are not Boolean values, it can still be considered a boolean operator since its return value can always be converted to a boolean primitive.

Слайд 9

IIFE
An IIFE (Immediately Invoked Function Expression) is a JavaScript function that

runs as soon as it is defined.

Слайд 10

SELF-EXECUTING ANONYMOUS FUNCTION
It is a design pattern which is also known

as a Self-Executing Anonymous Function and contains two major parts:
The first is the anonymous function with lexical scope enclosed within the Grouping Operator (). This prevents accessing variables within the IIFE idiom as well as polluting the global scope.
The second part creates the immediately invoked function expression () through which the JavaScript engine will directly interpret the function.