Ruby是我最喜欢的语言，以下是我不喜欢的语言:

绿色线程+阻塞C库=巨大的失败 慢得令人痛苦 标准库本身与其使用bang!方法 模块包含+扩展是混乱的。 “开放类”不能是范围-我想添加一个String#dostuff，但我不希望泄漏到所有的第三方库 没有二进制部署打包解决方案。

JavaScript

Function object syntax: f = new Function( "foo", "bar", "return foo+bar;" ); (It takes n arguments, the first n-1 are arguments for the function, then nth is the actual function, in string form. Which is just silly.) Function arguments can be repeated. f = new Function( "foo", "foo", "return foo;" ); The last repetition is the only one ever used, though: f( "bye", "hi" ) // returns "hi" f( "hi" ) // returns undefined E4X should just die. My users are always complaining that it doesn't work the way they think it will. Let's face it, when you need a page and a half of psuedocode for a setter, it's time to rethink things. A standard notion of stdin/stdout/stderr (and files!) would be nice. null != undefined It's irritating to have to handle them both. Sometimes it's useful, but most languages manage to limp along fine with one.

C#

Reference types are nullable by default; in-language null keyword is untyped. Lack of discriminated unions Exceptions as default, non-exceptional error handling method - there's not much of an alternative. archaic switch statement syntax and limitations Needless distinction between constructors + static methods Static methods can't be part of an interface Lack of by-shape interface implementation rather than explicit interface implementation - leading to numerous language design hacks such as the linq query syntax, foreach, collection & object initializers -- none of which can be flexibly reused. For example, the object initializer syntax may be nice, but plays poorly with immutable objects. Cannot inherit "interface" of a class independently of implementation - leading to code duplications and overarchitected code that provides interfaces, abstract base classes, a few common implementations, and no way to pick and choose the bits of each to use. Also; leads to too many code that's tightly coupled to a particular implementation since it's common to explicitly refer to the implementation type rather than an interface. Cannot multiply inherit via composition since a classes "interface" is tightly coupled to it's implementation; effectively lack of mixins. The above limitations of interfaces lead to a proliferation of virtually identical interfaces that don't overlap naturally in any kind of type hierarchy. IComparable vs. IEquatable vs. IComparable<T> vs object.Equals vs. operator == etc. etc. By extension, making a custom type that satisfies all these things is a lot more work than necessary (in particular for collection classes). Obviously, the language designers realize this, hence the various workarounds for things like linq, foreach and collection initializers which work by-shape rather than by-interface. Redundant use of parentheses and braces rather than layout-is-structure. Return values can be ignored, limiting the effectiveness of type inference. Enums aren't a normal type and can't have methods. Also, enum values aren't typesafe and may be initialized to 0 despite not having a 0 value. Mixing metaphors by lumping flag and non-flag enums together. Lack of proper value type support. Value types can't be inherited, have different constructor semantics, and perform poorly due to CLR limitations. Also, confusing semantics regarding value types: some values are really values (and can't be modified), and others are really non-aliased, non-null references (variables). This gets particularly confusing with regards to the next issue: Semantic distinction between fields and properties, particularly in conjunction with lack of mutability modifier (ala C++'s const) Can't specialize generics Cannot provide default generic type parameters (e.g. factory generics) lack of typedef makes generics a pain to use (using is a limited but good-to-know substitute!) Can't genericize over things other than types (e.g. functions, plain values, or names). This means you can't do something like make a generic implementation of a dependancy property leading to, well, nasty implementations of things like dependancy properties and the overuse of code-snippets and poorly readable code as a result. Limited capability to specify generic type requirements e.g. generic sum method that takes both int, double and a bigint (without tricky and often slow hacks). An interface method implementation or virtual method override cannot return a more specific type or accept a more general type; i.e. limited co/contravariance support even in C# 4.

C++

Strings. They are not interoperable with platform strings, so you end up using std::vector half of the time. The copy policy (copy on write or deep copy) is not defined, so performance guarantees can not be given for straightforward syntax. Sometimes they rely on STL algorithms that are not very intuitive to use. Too many libraries roll their own which are unfortunately much more comfortable to use. Unless you have to combine them. Variety of string representations Now, this is a little bit of a platform problem - but I still hope it would have been better when a less obstinate standard string class would have been available earlier. The following string representations I use frequently: generic LPCTSTR, LPC(W)STR allocated by CoTaskMemAlloc, BSTR, _bstr _t (w)string, CString, std::vector a roll-my-own class (sigh) that adds range checking and basic operations to a (w)char * buffer of known length Build model. I am sick to death of all the time spent muddling around with who-includes-what, forward declarations, optimizing precompiled headers and includes to keep at least incremental build times bearable, etc. It was great in the eighties, but now? There are so many hurdles to packing up a piece of code so it can be reused that even moms dog gets bored listening to me. Hard to parse This makes external tools especially hard to write, and get right. And today, we C++ guys are lacking mostly in the tool chain. I love my C# reflection and delegates but I can live without them. Without great refactoring, I can't. Threading is too hard Language doesn't even recognize it (by now), and the freedoms of the compiler - while great - are to painful. Static and on-demand initialization Technically, I cheat here: this is another puzzle piece in the "wrap up code for reuse": It's a nightmare to get something initialized only when it is needed. The best solution to all other redist problems is throwing everything into headers, this problem says "neeener - you cannot".

诚然，其中许多内容超出了严格的语言范围，但在我看来，整个工具链都需要进行判断和发展。

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)

C#

当被枚举的集合中的对象发生变化时，foreach命令弹出， UI控件吐出假人，因为它们在错误的线程上访问。当然是所有的调度员。调用可以移动到CLR管道， PInvoke，编组等， 我浪费了两年时间学习远程遥控， 它没有露比性感。