c#中缺少预处理器。

我知道他们把它放在一边是因为有些人会滥用它，但我认为他们把孩子和洗澡水一起倒掉了。代码生成被认为是一件好事，在c++中，预处理程序是我的第一个代码生成器。

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"?

Common Lisp

conditions aren't classes (since classes came later), even though their interface is almost identical some of the names are just weird, e.g., flet / labels (only difference: scope), and defvar / defparameter (only difference: behavior when already defined), or any of the bit-twiddling functions (dpb, ldb, etc.) packages are ... really hard to get right -- every time I think I understand them, they don't do what I want built-in data structures and functions aren't as generic as they could be (e.g., why can't I define my own hash function portably?) multiple namespaces for functions, variables, etc. (I'm not opposed to this in principle, but CL made it too complex; Norvig has said he can't tell from the spec but there appear to be at least 7 namespaces)

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。

第一个帖子，所以对我放松点:)…很棒的社区网站，顺便说一句!

我试着阅读其他所有的c#回复，这样我的回复就不会重叠了

c#……排名不分先后:

1) switch语句中的case没有fallthrough。如果没有转机……为什么必须显式的类型中断;呢?这只是弱智和令人困惑，因为它意味着没有休息的能力;!!

2)不能在子作用域中声明同名变量，但可以声明与类变量同名的变量?要么都允许，要么都不允许。否则，就没有意义了。

3)函数中没有可选/默认参数

4) finally{}中的异常应该隐式地捕捉每一行。或者至少，只有NullReferenceException异常。例如，在访问数据库后，应该总是清理。所以，finally块应该看起来像这样:

finally
{
  if(par1 != null)
    par1.Dispose();
  if(comm != null)
    comm.Dispose();
  if(conn != null)
    conn.Dispose();
}

如果可以写成这样，就会简洁得多:

finally
{
    par1.Dispose();
    comm.Dispose();
    conn.Dispose();
}

但是，不……你必须检查你是否正在访问一个空对象，否则它可能会从finally块抛出一个NullReferenceException。谁真的需要finally块中的异常呢?

5)泛型:你可以指定new()来实例化你的泛型对象，但是这个对象需要有一个默认构造函数。为什么不能指定一个签名，这样就不需要在还没有空构造函数的情况下创建空构造函数，而只使用已有的构造函数。

JavaFX

Type inference sometimes doesn't behave like you would expect, so you often need to explicitly declare the type. def behaves likes const in C and not final in Java you can insert a value in a sequence by accessing an index >= seq.length, which should actually throw a compiler error (according to the reference). if you assign null to a String, it defaults to "". If you assign null to an Integer, a compiler error is thrown (in contrast to what the reference says). handles CheckedExceptions the same way as RuntimeExceptions