Does JavaScript have an expression form of switch?

Question

When getting a value conditionally, I like to use the ternary operator (?:) so that I can have const variable declarations:

// Better
const foo = x ? 'bar' : 'goo';

// Worse
var foo;
if (x) {
    foo = 'bar';
} else {
    foo = 'goo';
}

I would like to do the same for switch statements. I can use a series of nested ?:, but this is quite cumbersome and does not scale well:

const foo = x === 1 ? 'bar' : (x === 2 ? 'goo' : 'zoo');

I could even use a closure, but this is also verbose:

const foo = (() => {
  switch(x) {
    case 1: 
        return 'bar';
    case 2: 
        return 'goo';
    default:
        return 'zoo';
  }
})();

Is there a switch expression in JavaScript?

Answer 1

You should first and foremost keep things readable and manageable. Squeezing two or three conditions with four or five values into one line is unreadable almost any way you turn it.

I'd suggest this very declarative approach:

let fooToBarMap = {
    foo: 'bar',
    baz: 42
};

let y = fooToBarMap[x] || 'default';