10 most interesting features of modern programming languages

With the rapid development of information technology, more and more programming languages are constantly appearing in our lives, while at the same time providing us with more job opportunities. Let's look at the age of programming languages: Lisp (1958), Smalltalk (1972), Objective-c (1984), Haskell (1990), OCaml (1996), and so on. These are the languages of the last century.

This article has selected several of the latest languages: Reason, Swift, Kotlin, Dart as a research object, summed up 10 features:

1 pipe operator Pipeline operator

Reason syntax

Let NewsCore = Me.score  |> double  |> (IT) + Add (7, it)  |> (IT) + boundscore (0, +, it);

The corresponding JavaScript notation:

Boundscore (0, +, add (7, double (Me.score)));

and ES has a corresponding proposal: Tc39/proposal-pipeline-operator

2 pattern matched to the pattern matching

Kotlin syntax

When (x) {in    1..10, print ("x is in the range")    validnumbers--Print ("x is valid")    !in 10..20-> ; Print ("X is outside the range")    else, print ("None of the above")}

3 Reactive (RX) programming build in the language

Dart syntax

Input.onkeydown                                                . Where ((e) = E.ctrlkey && E.code = = ' Enter ')                . ForEach ((e) = = Dispatch ( Addtodoaction (E.target.value));

4 default parameters for lambda functions

Kotlin syntax (using it as the default parameter)

Strings  . filter{it.length = = 5}  . map{it.touppercase ()}

Compare JavaScript

Strings  . filter{it = It.length = = 5}  . map{it = It.touppercase ()}

5 deconstructed destructuring

Reason Syntax:

Let someints = (ten, twenty) = Someints;type person = {name:string, age:int};let Someperson = {name: ' Guy ', Age:30};let {name, age} = Someperson;

Kotlin syntax

Data class person (Val name:string, Val Age:int) Val (name, age) = person ("guy", 20)

ES6 already has an array deconstruction, ES8 increases the object deconstruction

6 operator Cascade Cascade operator

Dart syntax

Queryselector (' #button ')//Get an object ...  Text = ' Confirm '//Use it members ...  Classes.add (' important '):  Onclick.listen ((e) = Dispatch (Confirmedaction ()));

The corresponding JavaScript notation

var button = queryselector (' #button '); button.text = ' Confirm '; Button.classed.add (' important '); Button.onClick.listen ((e) = Dispatch (Confirmedaction ()));

If you use jQuery basically in the same notation as DART, but the two are fundamentally different

7 IF-expression if expressions

Kotlin syntax

Val result = if (param = = 1) {    "one"} else if (param = = 2) {    "one"} else {    "three"}

For if expressions some people like, some hate, some people feel indifferent; I am very fond of, I have in the previous answer: Https://www.zhihu.com/questio ...

8 Try Expressions

Kotlin syntax

Val result = try {    count ()} catch (E:arithmeticex

ception) {throw illegalstateexception (E)
}

9 Automatic Automatic currying

Reason Syntax:

Let add = (x, y) = = x + y;   /* Same as (x) = = (y) + x + y; */let five = Add (2,3);         /* 5 */let alsofive = Add (2) (3);    /* 5 */let addfive = Add (5);           /* y = 5 + y; */let Eleven = addfive (6);            /* One */let twelve = addfive (7);     /* 12 */

10 Methods Extension Method extensions

Swift Syntax:

Extension Int {    func repetitions (Task: ()-Void) {for        _ in 0..<self {            task ()        }    }}3.repetit Ions ({    print ("hello!")}) hello!//hello!//hello!

JavaScript can be extended on the prototype.

I think there's a very useful feature to be given, optional-chaining. It is not mentioned, because most languages already have this feature, it seems that JavaScript development is still a bit slow.

These are the most interesting features of these 10 modern programming languages, and I hope you know something about it.