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// Copyright 2025 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// *********************************** ES2016
(() => {
// Exponentiation operator
let v = 2 ** 2;
v **= 3;
})();
// *********************************** ES2018
(() => {
// Async generators
async function* foo1() {
await 42;
yield 0;
}
async function foo2() {
for await (let a of b) {
bar1(x);
}
}
})();
(() => {
// Dotall regexp
/./s;
/./su;
})();
(() => {
// Named capturing groups regex
let v = /(?<month>\d{2})-(?<day>\d{2})/;
v.exec("11-11").groups.month;
})();
(() => {
// Rest
let { a, ...b } = { x: 1, y: 2, z: 3 };
// Spread
let v = { a, ...b };
})();
// *********************************** ES2019
(() => {
// Optional catch binding
try {
throw 0;
} catch {
foo();
} finally {
bar();
}
})();
(() => {
// Json strings - here: "a\u2028b"
"a
b";
})();
// *********************************** ES2020
(() => {
// BigInts
let v1 = 6n;
let v2 = BigInt(1234546) + v1;
let v3 = 0b1000011n;
})();
(() => {
// Nullish coalescing operator
object.foo ?? "42";
})();
(() => {
// Optional chaining
const obj = {
foo: {
bar: 42,
},
};
obj?.foo?.bar;
obj?.meh?.bar;
obj?.meh?.bar();
})();
// *********************************** ES2021
(() => {
// Numeric separator
let v1 = 1_000_000_000_000;
let v2 = 0b1010_0001;
})();
(() => {
// Logical assignment operators
let v = false;
v ||= true;
})();
// *********************************** ES2022
(() => {
// Private methods and properties
// Private property in object
class Foo {
#xValue = 0;
get #x() {
return this.#xValue;
}
set #x(value) {
this.#xValue = value;
}
#inc() {
this.#x++;
}
baz(obj) {
return #xValue in obj;
}
}
})();
(() => {
// Class properties
class Foo {
prop = "42";
fun = () => {
return this.prop;
};
static staticProp = "42";
static staticFun = function() {
return Foo2.staticProp;
};
}
})();
(() => {
// Class static block
class Foo {
static #a = 42;
static b;
static {
this.b = bar(this.#a);
}
}
})();
// *********************************** ES2024
(() => {
// Unicode sets regex
/[\p{Decimal_Number}&&\p{ASCII}]/v;
})();
// *********************************** ES2025
(() => {
// Duplicate named capturing groups regex
let v = /(?<month>\d{2})-(?<year>\d{4})|(?<year>\d{4})-(?<month>\d{2})/;
v.exec("11-1111").groups.year;
})();
(() => {
// Regexp modifiers
/(?i:a)a/;
/(?m:^a)a/;
/(?s:.)./;
/(?im:^a)a/;
})();
// *********************************** Proposals
(() => {
// Do expressions
let v = do {
if (v) {
("1");
} else {
("2");
}
};
})();
(() => {
// Explicit resource management
async function foo() {
using sync = openSync();
await using async = await openAsync();
}
})();
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