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.

F#

Type inference is limited. It propagates forward only. F# won't try to infer an object type based on the methods and properties used: you'll get "lookup of indeterminate object type" errors when it doesn't have a clue. One cannot mix floats and ints: 1 + 2.3 is a type error. It's a little awkward to have to create a builder object in order to define a monad or computation expression. In Haskell or Scala, you can define the monad operations directly on the monadic object. Though the #light syntax is preferred, the indentation rules are sometimes not very intuitive or become cumbersome.

c# / .net:

Classes should be sealed by default There should be no lock statement - instead, you should have specific locking objects, and there should be methods such as Acquire which return disposable lock tokens. Corollary: there shouldn't be a monitor for every object. GetHashCode() and Equals() shouldn't be in System.Object - not everything's suitable for hashing. Instead, have an IdentityComparer which does the same thing, and keep the IComparer<T>, IComparable<T>, IEqualityComparer<T> and IEquatable<T> interfaces for custom comparisons. Poor support for immutability Poor way of discovering extension methods - it should be a much more conscious decision than just the fact that I'm using a namespace.

这些都是我想出来的，明天问我，我会想出一个不同的5个:)

PHP:

1)强迫我创造不必要的变量:

$parts = explode('|', $string);
$first = $parts[0];

2) lambdas的实现如此蹩脚，它大致相当于使用eval()，而且如此糟糕，我从未使用过它(参见http://www.php.net/create_function)。

3) try/catch系统只能捕获大约80%可能发生的错误。

4) Regex支持和lambda支持一样蹩脚，因为它必须在常规字符串中编写，这使得最难学的编程工具之一变得困难了三倍。PHP应该是一种“简单”的语言吗?

5)没有办法安全地从$_POST中取出东西，而不写两次或构建自己的函数，或使用'@'操作符:

$x = isset($_POST['foo']['bar']) ? $_POST['foo']['bar'] : null;

6)额外答案:“@”。如果你懒得写正确的代码，那就添加'@'，这对以后调试你的代码的人来说太糟糕了。

我使用Java，我最大的不满是字符串操作的低效率。当你使用+运算符时。说真的，难道编译器不能计算出我添加了多少字符串，然后在后台为我生成StringBuffer的东西吗?

通常，使用+的代码比StringBuffers操作序列更具可读性。

另外，我讨厌本机数组和集合框架之间的冗余。. toarray()的语法极其丑陋。

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)。