How to use the Null conduction operator in Ruan Yifeng es6.
const firstName = message?.body?.user?.firstName || 'default';
寫(xiě)了這句之后直接編譯出錯(cuò)了。
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This syntax is js 的么？感覺(jué)是 coffee 的，即使 js 有，應(yīng)該也得有引入對(duì)應(yīng)的presets 到babel，es6好像沒(méi)有這種語(yǔ)法，引入最新的babel presetTry to see if it can be compiled
Mentioned in the article. "Null Conduction Talisman" is just a proposal. Babel is not displayed yet.
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