Fixing JSON

I never understood why the double quotes around property names are mandatory. For example, in JavaScript, I can write

    { foo: 1, bar: 2 }

but JSON syntax insists on

    { "foo": 1, "bar": 2 }

This makes JSON less easily readable by humans, and harder to write or edit by hand.

Anyone know why JSON was designed this way?

My assumption is that quotes are needed for keys with spaces.

    > x = {}
    > x["foo bar"] = 1
    > x
    { 'foo bar': 1 }