BrainF * ck

你的亮点是图灵完备?!我可以在Perl正则表达式中做更多的事情! 缺少对象。来吧,人!就像，你好… 没有网络库。我只想刮一个网页，天哪。 没有一级函数。恭喜你——你可以同情你的Java朋友了。 一个无限的磁带存储，没有其他。这是如此的矫情，我们可能还在写Lisp。

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.

REBOL

REBOL是我最喜欢的语言之一。我不能说我有一个最喜欢的，尽管Haskell排名也很高。

Its odd syntax scares off many developers before they even give it a try. use [email rules url] [ ; A small DSL that sends email to people about URLs. rules: [ some [ into [ set email email! set url url! (send/subject email url reform [ "Check Out" url ]) ] ] ] ; Global context notify: func [ [catch] dsl [block!] ] [ unless parse dsl rules [ throw make error! "You screwed up somehow." ] ] ] notify [ [ a@b.com http://www.google.com ] [ b@c.com http://www.yahoo.com ] ] Recursive dialects are very easy to validate with PARSE but very difficult to evaluate. (Stacks can be helpful here.) REBOL has very poor integration with many popular technologies, particularly XML. I suspect this is partly arrogance, because the REBOL BLOCK! datatype can do almost everything XML can do. However, the real world has XML in it. No Unicode. Thanks to AltMe, REBOL's user community is very insular. I can understand why they want to use AltMe. It's written in REBOL and shows off its strengths. Unfortunately it also puts them off on their own little island.

即将到来的REBOL 3有望解决许多这些问题，除了最后一个。

Lua

If you do foo.bar(1,2) then 'self' is nil inside the bar method. You must remember to do foo:bar(1,2) instead. I'd rather have that switched ('self' should be defined by default unless you use the ':' operator, or you call a function that isn't a method). Variables are global by default. I'd rather ditch the 'local' keyword and have a 'global' one instead. Undeclared variables are assigned the nil. I'd rather receive an error message. You can sidestep this by manipulating the global env's metatable, but I'd rather have it implemented by default and be able to deactivate it. Multiple returned values on parameters are not handled very nicely. Say you have a function foo() that returns 1,2,3 (three values) and bar() returns 4,5 (two values). If you do print(foo(),bar()) you will get "1,4,5" ... only the "last" tuple is expanded on calls. The # (table length) operator only works in tables indexed with continuous integers. If your table isn't like that and you want to know how many elements does it have, you need to either parse it with a loop, or update a counter each time you insert/remove an element from it.

Python (3.1)

奇怪的无序T if C else F语法用于条件语句。 字节字面值看起来太像STR字面值了。我们应该得到x'414243'而不是b' abc '。 str在某些平台上是UTF-16，在其他平台上是UTF-32。(尽管至少比2要好。x字符串。) 具有相同的加法和连接运算符。这对numpy.array这样的类型很不利。 运行缓慢。

我讨厌c++的五个方面

联系时间。使用分布式构建，我可以在同一时间重新构建我们的整个项目，它需要我们的链接器运行。 没有防止内存操作重新排序的标准方法。使用写组合内存通常需要滥用volatile关键字。防止读重排序(在处理SIMD数学管道时通常是优化的关键)通常是通过在例程中间注入空ASM块来实现的。 多步宏来解决字符串化问题:

#define STR_LINE2(x) #x
#define STR_LINE(x)   STR_LINE2(x)
#define LINE_NUMBER STR_LINE(__LINE__)

做字符串操作通常是很痛苦的。 大量的非标准化printf变体(vsnprintf_s vs _vsnprintf_s)。