JavaScript type tests

by Town March 07, 2018

JavaScript

var test = {};
test.inner = {};

if (test !== undefined) {
console.log("test is populated");
}
if (test === undefined) {
console.log("test is undefined");
}
if (test.inner === undefined) {
console.log("test.inner is undefined");
}
if (test.inner !== undefined) {
console.log("test.inner is populated");
}

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JavaScript type tests

JavaScript

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Use pre-released features

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Private collections and fiddles

Console