Syntax

The grammar of JavaScript.

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The destructuring assignment syntax is a JavaScript expression that makes it possible to unpack values from arrays, or properties from objects, into distinct variables.

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💡

The Export button at the top of each block lets you get the raw JSON data for any chart, or a GraphQL query you can run against our public API.

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Spread syntax (...) allows an iterable such as an array expression or string to be expanded in places where zero or more arguments (for function calls) or elements (for array literals) are expected, or an object expression to be expanded in places where zero or more key-value pairs (for object literals) are expected.

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An arrow function expression is a compact alternative to a traditional function expression, but is limited and can't be used in all situations.

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We asked members of the JavaScript community to share their “pick of the year”

My 2020 Pick: A11y Coffee

This is a fantastic intro resource for learning about web accessibility! I picked it because it's our job as JS devs to make sure that the sites we build are usable by everyone, not just sighted keyboard-and-mouse users.

We asked members of the JavaScript community to share their “pick of the year”

Josh W. Comeau

Software-engineer-turned-educator
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The nullish coalescing operator (??) is a logical operator that returns its right-hand side operand when its left-hand side operand is null or undefined, and otherwise returns its left-hand side operand.

2020

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The ?. operator functions similarly to the . chaining operator, except that instead of causing an error if a reference is nullish (null or undefined), the expression short-circuits with a return value of undefined.

2020

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Private Fields
Completion percentage: 95.9% (22786)
Completion percentage: 95.9% (22786)

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Class properties are public by default and can be examined or modified outside the class. There is however a stage 3 proposal to allow defining private class fields using a hash # prefix.

2020

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Recommended Resources

Professional JavaScript Learning Path

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