关于c#:

I hate that there is no keyword to specify which exceptions are thrown from a method like in java. Its a much better way to document exceptions than using an XML comment. I would also want a much better syntax for generic constraints like oring and anding of constraints. Why a method can't return more than one value? Lack of support for aspect oriented programming in the language. Why can't you annotate each one of the property accessors with an attribute? Lack of builtin regexp support like in perl.

我讨厌Java的五个方面:

没有一级函数。 没有类型推断。 缺乏理智的默认值在eg图形。 NullPointerException不包含更多关于什么是null的信息。 毫无意义的“可配置”框架/服务提供者接口/工厂类/依赖注入系统的激增。可配置性几乎从未使用过，严重违反了DRY，代码的大小增加了四倍，易读性减少了一半。

我知道，我应该试试Scala。

Python:

我仍然是python的一般用户，所以我的抱怨可能只是知识的锁或误用。欢迎提出意见。我很喜欢这门语言。

Poor thread support and GIL. If you'd like to take use of multicore platform, most of the python programmers would probably recommend multiprocessing or some sort, don't use threading. It wouldn't give you the performance you are expecting. property only for instance variable. _class_var = property(classmethod(some_method)) just wouldn't work. How can I get a property wrapped class variable? no access control. All access controls are syntax mangling. Like private is __private, protect is _protected, etc... And hope that everyone programs python follows the naming convention. Come on, we can do better than that. I agree the python philosophy of being simple and clear syntax but some simple and clear syntax not being supported seems lock of good judgement, in my opinion. Such as, a++, ++a, a-- and --a, self-de/increment, what's wrong with those? foo = (a > b ? a : b) unary operation, what's wrong with those? (I know py2.6 has something similar introduced, but given the massive support of almost every other language for those simple syntax, why reinventing the wheel? why not just follow the best practice? Shouldn't a good thing just keep in its good "form"?) Program to interface. Python has no interface or abstract class concept (py3k has something called abc), everything is concrete. Providing an "interface" or "abstract" keyword to build class skeleton and guard class inheritance and extension wouldn't be a bad idea I think. It helps on top-down design. Currently, I just have to fill the each of methods with NotImplementedError, quite a tedious job. I have to add this. version less than 3.x has str and unicode types. This is a true nightmare. It makes ascii and non-ascii/unicode mixing most likely to fail (bad, bad)

我看到人们抱怨速度。我不明白。它是一种解释语言，代码直到运行时才编译成机器代码，这就是它的本质。你不能比较解释语言和编译语言的速度。据我所知，在解释/脚本语言中，python并不慢。

C#

泛型参数是不变的，c# 4.0为泛型类型引入了协方差和逆变性 可覆盖的类成员必须显式地标记为virtual

Java

缺少无符号数字数据类型 基本数据类型不是对象

Python:

Too slow! list operations don't return the list, so you can't do list.append(4).append(5). (I mean a reference to the same list, not a copy). This is a minor gripe; it's only come up a few times. statements don't return values (if, print, while, for, etc). This is only a problem when dealing with lambdas. lambdas can only be one expression. There's no real need for this restriction, as they are equivalent to functions in every other way. What if I want a button press event which calls two functions? I'd need to create a named function to supply that functionality to an action listener, while doing "lambda: f1(); f2()" would not hurt. you can only put standard a-zA-Z_0-9 as names. Having functions like "true?" and "+" would be great. Of course, this could lead to terrible obfuscation, but I'm not saying we immediately rename all functions to "p@$%3". Which do you find clearer to read: "dec2bin" or "dec->bin"? ("store_results" or "storeResults") or "store-results"?

Objective Caml

缺少名称空间。 啰嗦类和对象注释。 复杂的构建系统。 不方便制作中缀。