>>99 p *[1,2,3,4].each

>>89 JavaScriptにはクラスがありません、なのでrubyで書けばこのような簡潔なコードでもJavaScriptでは非常に長くなります。

# ruby
class A
attr_accessor :name
def initialize name
@name = name
end
end
p A.new("uy").name

↓

# JavaScript（笑）
(function(Opal) {
Opal.dynamic_require_severity = "error";
var self = Opal.top, $scope = Opal, nil = Opal.nil, $breaker = Opal.breaker, $slice = Opal.slice, $klass = Opal.klass;
Opal.add_stubs(['$attr_accessor', '$p', '$name', '$new']);
(function($base, $super) {
function $A(){};
var self = $A = $klass($base, $super, 'A', $A);
var def = self.$$proto, $scope = self.$$scope;
self.$attr_accessor("name");
return (def.$initialize = function(name) {
var self = this;
return self.name = name;
}, nil) && 'initialize';
})(self, null);
return self.$p($scope.get('A').$new("uy").$name());
})(Opal);