function functions(object) {
      return object == null ? [] : baseFunctions(object, keys(object));
    }
Creates an array of function property names from own enumerable properties
of `object`.

@static
@since 0.1.0
@memberOf _
@category Object
@param {Object} object The object to inspect.
@returns {Array} Returns the function names.
@see _.functionsIn
@example

function Foo() {
  this.a = _.constant('a');
  this.b = _.constant('b');
}

Foo.prototype.c = _.constant('c');

_.functions(new Foo);
// => ['a', 'b']