Ruby

无类型推断 方法/函数不是一级对象 变量的范围不是词法的，尽管块变量的范围是词法的 Def内部的Def super和super()的区别

C#.

我最讨厌的是:

No multiple inheritance - imagine you could provide whatever GUI framework base class (Control, Window, whatever) with MVC - related stuff, etc... framework / base class agnostic! No "friend" keyword... I know, the RAD - victims would abuse it for all kinds of stinky code and for hilarious malpractices, but it would be nice for the OOD - guys to enforce the law of demeter No language integrated DBC features, there are the Contracts, but I would rather have that Spec# - style with a general purpose "!" - postfix operator No AOP (I don't get it... this language has attributes, it would have been SO EASY to add interception code in the compiler!) No weak event delegates - the observer pattern becomes nothing but a memory leak bait as it is now... :-(

Haskell:

空间泄漏——懒惰的默认代价——也许代价太高了? 甚至像head和tail这样的纯函数也会调用错误并引导您进入IO。 fail from Monad -带回MonadZero。 Num类-(+)应该在AdditiveGroup或类似的类型中。 那个单子不是一个应用程序。

Ruby。

Strange scoping rules - variables, constants, and methods each behave differently from each other. The rules change also depending on which keyword you used to create a closure. Or on whether you're in a class, eigenclass, object, module, or module's self. Then there's instance_eval, which changes the rules to a different set of rules. And they change again when a module is "included" or "extended", which themselves do different things to scope. And some sets of rules can't be emulated by metaprogramming, so you have to use eval. Unless you're on ruby 1.9, where all of this is different. Namespacing is basically useless. If you have Foo::File, then the stdlib File is probably broken for all of Foo. require statement is broken. If two files require eachother, the behavior of those files can change dramatically depending on which is loaded first from elsewhere. libraries change APIs dramatically and suddenly, so you have to require specific minor revision numbers of all of your dependencies. For every single ruby application on your system. The rubygems package system overrides "require" rather than putting files in the search path - because why use a system when you can replace it?

C++

编写一个简单的代码片段要花很多时间。 对于(std::vector::const_iterator iter =[…] Vector.remove()不移除。 Vector.push_front()不存在。 头文件 没有λ 如果至少有一个虚函数，则没有自动空虚析构函数。

C++

cryptic error-messages when templates are involved lack of template constraints (many cases can be worked around with template metaprogramming, but this will result in unreadable code (at least for average programmers) in most cases) pointer to member-function syntax c++ standards committee should release offical standards more often (or at least release separate updates to the standard library itself), i mean really TR1 was released 2005, and we still dont have a shared_ptr, bind and alike in the standard library. -