C#

它是一种很棒的语言，特别是在LINQ中，但是与c++相比泛型支持较差。它有如此多的潜力，但目前的实现只对强类型集合和类似的琐碎事情有用。下面举几个例子:

A generic argument cannot be restricted to enums (only classes or structs). A generic argument cannot be a static class. Why? This seems like a completely artifical restriction. You cannot specify that a generic type must have a constructor with a certain signature because you cannot have constructors on interfaces. Why not? It's just another method with the special name ".ctor". Similarly, you cannot specify that a generic type must have a static method, because those also cannot be declared on interface. Something like static T Parse(string s) would often come in useful. The compiler is too eager in prohibiting some casts which the programmer knows would actually work, so they require uglyness like (TheRealType)(object)value No covariance, eg. IList<string> cannot be converted to IList<object>, even though string[] can be converted to object[]. (Microsoft might be fixing this in C# 4.0, though.)

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#

Lack of multiple dispatch based on the runtime type of the method arguments. dynamic should solve most of this, but it hasn't been released yet. Interface implementation is declarative not structural. I really like the way Google's Go language is doing types Making asynchronous method calls is really bulky (and I'm pretty sure all threads are OS threads, not lightweight threads) No macro system. I'm not talking about C-style macros here; I'm talking LISP/Scheme style macros Operators are static methods and their signatures are overly constrained (and you can't create new ones).

Python:

缺少静态类型 默认参数处理(特别是可以为未来的调用者更改默认参数的事实!) 需要的下划线太多(构造函数必须调用__init__) 缺少适当的私有成员和函数(惯例只是说大多数以下划线开头的东西都是私有的，除了像__getattr__这样的东西不是) 有趣的打印到文件的语法(但他们在Python 3中修复了这个问题)

ColdFusion

大型Flash表单的编译时间。 动态变量类型(有时我讨厌它们) CFScript缺乏特性。 CFTable(永远不能正确显示)。 CFChart中缺少图表类型。 完全缺乏NTLM支持(企业就绪-是的) cfc中的低能变量作用域 没有一个真正的NULL的概念-你的变量只是消失! 没有办法测试某些东西的存在(比如作用域，只是它们内部的成员)

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。