最近Stack Overflow上有一群讨厌perl的人,所以我想我应该把我的“关于你最喜欢的语言你讨厌的五件事”的问题带到Stack Overflow上。拿你最喜欢的语言来说,告诉我你讨厌它的五件事。这些可能只是让你烦恼的事情,承认的设计缺陷,公认的性能问题,或任何其他类别。你只需要讨厌它,它必须是你最喜欢的语言。

不要拿它和其他语言比较,也不要谈论你已经讨厌的语言。不要用你最喜欢的语言谈论你喜欢的事情。我只是想听到你讨厌但能容忍的东西,这样你就可以使用所有其他的东西,我想听到你希望别人使用的语言。

每当有人试图把他们最喜欢的语言强加给我时,我就会问这个问题,有时是面试问题。如果有人找不出他最喜欢的工具的5个缺点,那他对它还不够了解,不能提倡它,也不能利用它赚大钱。他还没有在足够多的不同情况下使用它来充分探索它。他把它作为一种文化或宗教来倡导,这意味着如果我不选择他最喜欢的技术,我就错了。

我不在乎你用什么语言。不想使用特定的语言?那就不要。你通过尽职调查做出了明智的选择,但仍然没有使用它?好吧。有时正确的答案是“你有一个强大的编程团队,有良好的实践和丰富的Bar经验。改成Foo是愚蠢的。”


This is a good question for code reviews too. People who really know a codebase will have all sorts of suggestions for it, and those who don't know it so well have non-specific complaints. I ask things like "If you could start over on this project, what would you do differently?" In this fantasy land, users and programmers get to complain about anything and everything they don't like. "I want a better interface", "I want to separate the model from the view", "I'd use this module instead of this other one", "I'd rename this set of methods", or whatever they really don't like about the current situation. That's how I get a handle on how much a particular developer knows about the codebase. It's also a clue about how much of the programmer's ego is tied up in what he's telling me.

憎恨并不是衡量人们了解多少的唯一尺度,但我发现它是一个相当不错的尺度。他们讨厌的事情也让我知道他们对这个话题的思考有多好。


当前回答

TCL

这是我最喜欢的语言,几乎可以做任何事情。多年来,它已经(慢慢地,非常缓慢地)演变为解决大多数让我烦恼的事情。而且这门语言非常灵活,很容易实现语法来覆盖那些仍然困扰我的东西。但是语言中有一些东西是不能轻易改变的,只是打破了它的禅意:

Arrays (of the associative kind, what Perl calls hash) don't have proper value semantics. This makes them awkward to pass to and return from functions. Also, this means that they can't be nested. For this reason dicts (dictionaries) were invented but too late, the nice array access syntax: $array($foo) is now forever taken by stupid arrays for backwards compatibility. We're now stuck with: dict get $dict $foo which is much more verbose and to me feels less readable. No real closures. Though it can be emulated somewhat by globals or namespaces but that defeats the reason for closures in the first place. Although, I can't really see for now how closures can be implemented in a pure value semantics system. Teacup is hard to use and is not at all intuitive compared to all other repository tool out there. This is more ActiveState's fault than tcl-core and doesn't really break tcl's Zen when coding but it is still very annoying.

其他回答

Lua:

The built-in error system is absolutely horrendous You can implement a try-catch system by modifying the Lua interpreter; but it has no compatibility with the errors that are thrown by the built in functions. The fact they have __newindex instead of __setindex as the setter ... and __newindex is only fired when the key doesn't already exist. If it does, no metamethod is called at all. No good type comparison system. There's the type() function but it only handles the basic types (all tables are tables). It really needs to have a metamethod for type comparisons. I've implemented this before with an 'is' operator and a __type metamethod and it works really nicely. It's a bitch to define new keywords. You can do it, but the code inside Lua isn't well documented so it's kind of trial and error to find out how to get the result you want. This is a major issue when you want to implement the things I mentioned above yourself (not so much __setindex though, that's an easy modification). I can't use it in a web browser. Yeah not really a problem with the language itself, but damn, would I love to be able to use Lua instead of Javascript... :)

Python:

没有分隔符表示块的结束会导致歧义,这样自动缩进就不能处理格式不佳的代码。 没有宏(修饰符不算) 没有像haskell的cabal或perl的CPAN那样的库自动获取 不能声明变量const(是的,可以自己定义变量,但是…) 元编程被削弱 差点忘了全局解释器锁

Oracle SQL

DUAL表。 不能通过别名分组。 我永远记不住分析函数的语法,所以我忘记/懒得使用它们。 缺少组合的LIKE和IN条件运算符。(不过,在10g之后,有一个REGEX_LIKE操作符可以做到这一点。) 笨拙的连接语法。

SQL并不是我最喜欢的语言,但它是我每天使用的三大语言之一。可能还有更多的项目,但这些是我脑海中最重要的。

我有一大堆SQL*PLUS的问题。我写了一个Perl的替代品,从命令行做我想做的,我使用sql。Emacs中的el用于交互式SQL会话。这些工具可以帮助我解决SQL*PLUS问题。


说到这里:

Perl

"Only perl can parse Perl." (But this is mostly an issue in syntax highlighting, which I don't prefer to use much anymore for any language.) I'm sometimes surprised by "the simple (but occasionally surprising) rule...: It looks like a function, therefore it is function, and precedence doesn't matter." (From perlfunc(1)) Dereferencing complex data structures can be confusing at times. I can't decide if this is a true flaw in Perl or just a consequence of having really powerful data structure facilities. Either way, I can normally get it right by taking a few minutes to think about what I'm doing. No option to cause system calls to raise their errors like the DBI module. (Thanks to brian d foy, I now know the autodie module on CPAN does this, but I'd like it built-in.) Warnings and strictures not enabled by default in scripts. (The -e option would turn them off for command line use.)

同样,肯定还有更多的事情,但这些是我最近注意到的问题。我还要加上=over and =back和古怪的L<…>语法在POD中,但也许那应该是一个单独的列表。


现在来看看三连冠:

康壳牌

Sourcing a file with arguments replaces the values of the parent script's arguments. (Executing . file arg1 puts arg1 in $1.) ksh is not an ideal interactive shell and defaults to vi key-bindings, rather than emacs. (My solution is to use bash for interactive shells.) Common utilities (such as grep) are implemented differently across different platforms thereby preventing perfect portability. Some useful commands need to be installed on some platforms and are part of the OS core on others. The syntax for conditionals is overly heavy. (if [ ... ]; then ... fi) Although it is Turing Complete, you are eventually going to want to move up to a more expressive language like Perl.

第4个问题的一个解决方案是习惯短路评估:

[ ... ] && ...

VB6

仅Windows。 不再支持。 数组可以从任何数字开始,而不是全部归一化为0。 已编译的应用程序依赖于许多dll才能正常运行。 许多复杂的控件(如浏览器控件或复杂的代码段)在运行未编译的代码时往往会破坏IDE,但在编译后却可以正常工作。

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.