What do you mean by the expressiveness of a programming language?

Question

I see a lot of the word \'expressiveness\' when people want to stress one language is better than the other. But I don\'t see exactly what they mean by it.

• Is it

Answer 1

Wikipedia has a bit about the concept. I myself take it to mean that a language can accomplish more with less (the so called "informal usage" in the Wikipedia article).

I consider JavaScript expressive (though this could be because Douglas Crockford drilled that idea into my noggin) because it can do so much with just a few keywords. For instance, the function keyword is a function, as well as a method, a class, and a lambda.

Some code illustration (leaving out some details for brevity) in JavaScript. It's an event class I wrote:

SJJS.util.Event = (function() {
    var _listeners = [];
    var _listenerReturns = [];

    return {
        addDomListener: function(element, eventName, listener) {
        },
        trigger: function(element, eventName) {
        },
        removeListener: function(eventlistener) {
        }
    }
})();

With just function, var, and some curly braces and parentheses I made a static class with methods and private variables.