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General shorthand checking in JavaScript

The shortened form of checking works for other data types as well. In this case, this data is first converted to a boolean type, and then compared with true. See an example:

let test = 3;

if (test) {
	console.log('+++'); // it will work
} else {
	console.log('---');
}

In fact, the above code is equivalent to the following:

let test = 3;

if (Boolean(test) === true) {
	console.log('+++');
} else {
	console.log('---');
}

Without running the code, determine what will be output to the console:

let test = 3;

if (test) {
	console.log('+++');
} else {
	console.log('---');
}

Without running the code, determine what will be output to the console:

let test = 'abc';

if (test) {
	console.log('+++');
} else {
	console.log('---');
}

Without running the code, determine what will be output to the console:

let test = '';

if (test) {
	console.log('+++');
} else {
	console.log('---');
}

Without running the code, determine what will be output to the console:

let test = 3 * 'abc';

if (test) {
	console.log('+++');
} else {
	console.log('---');
}

Without running the code, determine what will be output to the console:

let test = null;

if (test) {
	console.log('+++');
} else {
	console.log('---');
}

Without running the code, determine what will be output to the console:

let test = false;

if (test) {
	console.log('+++');
} else {
	console.log('---');
}

Without running the code, determine what will be output to the console:

let test;

if (test) {
	console.log('+++');
} else {
	console.log('---');
}

Without running the code, determine what will be output to the console:

let test = 0;

if (test) {
	console.log('+++');
} else {
	console.log('---');
}

Without running the code, determine what will be output to the console:

let test = '0';

if (test) {
	console.log('+++');
} else {
	console.log('---');
}

Without running the code, determine what will be output to the console:

let test = -1;

if (test) {
	console.log('+++');
} else {
	console.log('---');
}

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