Scala是我最喜欢的语言。五件讨厌的事?容易:

Takes a long time to learn properly. I know you can write Scala as a 'better java'. That is what we used to say about C++ and C too. I agree this is an inevitable consequence of the deep ideas in the language. But still ... Methods vs. Functions: def f(x: Int) = x*x defines a method f, not a function f. Methods are not functions despite a lot of early Scala tutorial material blurring the distinction. The language tries to blur it too because if you supply a method in some places where a function is expected it is accepted. Do we have to have both methods and functions? Yes it is fundamental. But it was initially confusing to me. Composing classes or objects from mixins in the 'cake' pattern is prone to NPE's. e.g. trait X { val host: String; val url = "http://" + host } is a mixin that will NPE on instantiation, or not, depending on its position in the class declaration. The compiler could tell you if it will fail but doesn't. (In 2.7 anyway.) It is hard to diagnose the problem in complex inheritance graphs. Arrays in 2.8 rely on implicits to mesh with the main scala collection types. But implicits are not applied everywhere. An Array can be supplied where a Seq is expected. But an Option[Array] cannot be supplied where an Option[Seq] is expected. I know there are no completely 'right' ways to handle java Arrays. Type erasure. Enough said.

Ruby有许多与速度相关的缺陷，但我并不讨厌它们。它也有社区传福音过度的缺陷，但这并没有真正困扰我。以下是我最讨厌的:

Closures (blocks) have 4 different creation syntaxes, and none of them are optimal. The elegant syntax is incomplete and ambiguous with hashes, and the full syntax is ugly. The community tends to be against real documentation, favoring ‘read the code’. I find this childish and lazy. Metaprogramming abuse, particularly in libraries, makes bugs a nightmare to track down. On a related note, pervasive metaprogramming makes a comprehensive IDE difficult, if not impossible, to make. The way block passing to functions is done is silly. There is no reason blocks should be passed outside the parameter list, or have odd special syntax to access (yield). I am of the opinion that blocks should have been given a less ambiguous syntax (or hashes could have used different delimiters; perhaps <> rather than {}), and passing as parameters to methods should have been just like all other parameters. object.method(1, {|a| a.bar}, "blah") These oddities, like the block must be the last parameter passed and passing more than one block is different with longer syntax, really annoy me.

我偶尔会用我喜欢的PHP，而Python会用得太多。

No namespace; everything is in a kind of very big namespace which is hell in bigger environments Lack of standards when it comes to functions: array functions take a needle as a first argument, haystack as second (see array_search). String functions often take the haystack first, needle second (see strpos). Other functions just use different naming schemes: bin2hex, strtolower, cal_to_jd Some functions have weird return values, out of what is normal: This forces you to have a third variable declared out of nowhere while PHP could efficiently interpret an empty array as false with its type juggling. There are near no other functions doing the same. $var = preg_match_all('/regexp/', $str, $ret); echo $var; //outputs the number of matches print_r($ret); //outputs the matches as an array The language (until PHP6) does its best to respect a near-retarded backward compatibility, making it carry bad practices and functions around when not needed (see mysql_escape_string vs. mysql_real_escape_string). The language evolved from a templating language to a full-backend one. This means anybody can output anything when they want, and it gets abused. You end up with template engines for a templating language... It sucks at importing files. You have 4 different ways to do it (include, include_once, require, require_once), they are all slow, very slow. In fact the whole language is slow. At least, pretty slower than python (even with a framework) and RoR from what I gather.

不过，我仍然喜欢PHP。这是网页开发的电锯:你想要一个小型到中型网站的速度非常快，并确保任何人都可以托管它(尽管配置可能不同)?PHP就在那里，它无处不在，只需要5分钟就可以安装一个完整的LAMP或WAMP堆栈。好吧，我现在要回去用Python工作了……

C

字符串操作。

必须手动处理字符串缓冲区是一个容易出错的痛苦。由于如此多的计算实际上是移动和修改字符串(计算机并不像人们想象的那样用于大型数字运算)，因此能够使用托管语言或c++的字符串对象来处理这些非常好。当我必须在直发C时，感觉就像在流沙中游泳。

C#

No easy way to check if a type is Numeric It means you are probably stuck using most of the microsoft stack, IIS and MSSQL Instead of being a specific tool for a specific problem, C# tries to be a language for every paradigm. Lack of community. Sure, there are starting to be open-source frameworks and libraries for C#. The same ones that have been available to Java developers for years. Hard to find good help. The internet is littered with poor examples of how to solve problems with C#. This goes back to problem #3.

Ruby。

Strange scoping rules - variables, constants, and methods each behave differently from each other. The rules change also depending on which keyword you used to create a closure. Or on whether you're in a class, eigenclass, object, module, or module's self. Then there's instance_eval, which changes the rules to a different set of rules. And they change again when a module is "included" or "extended", which themselves do different things to scope. And some sets of rules can't be emulated by metaprogramming, so you have to use eval. Unless you're on ruby 1.9, where all of this is different. Namespacing is basically useless. If you have Foo::File, then the stdlib File is probably broken for all of Foo. require statement is broken. If two files require eachother, the behavior of those files can change dramatically depending on which is loaded first from elsewhere. libraries change APIs dramatically and suddenly, so you have to require specific minor revision numbers of all of your dependencies. For every single ruby application on your system. The rubygems package system overrides "require" rather than putting files in the search path - because why use a system when you can replace it?