Edit fiddle - JSFiddle - React, Tailwind, and code Playground

JSFiddle - React, Tailwind, and code Playground

JavaScript

function minhaFn(nr) {
    return new Promise((resolve, reject) => {
        // isto vai dar asneira pois a variavel "naodeclarado" não está declarada
        resolve(nr / naodeclarado);
    });
}

minhaFn(20).catch(err => {
    if (err) {
        console.log(err);
        if (err.message.includes('is not defined')) {
            alert('Há variáveis não defenidas!');
        }
    }
}).then(res => console.log(res))

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JSFiddle - React, Tailwind, and code Playground

JavaScript

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