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TypeScript 3.7 RC & Nullish Coalescing

null, undefined default value

https://devblogs.microsoft.com/typescript/announcing-typescript-3-7-rc/#nullish-coalescing


let x = foo ?? bar();

// Again, the above code is equivalent to the following.

let x = (foo !== null && foo !== undefined) ?
    foo :
    bar();



// The ?? operator can replace uses of || when trying to use a default value. 

function initializeAudio() {
    let volume = localStorage.volume || 0.5
    // ...
}



refs

https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-7.html#nullish-coalescing



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原文地址:https://www.cnblogs.com/xgqfrms/p/11749345.html