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。
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:
[ ... ] && ...
C++
Strings.
They are not interoperable with platform strings, so you end up using std::vector half of the time. The copy policy (copy on write or deep copy) is not defined, so performance guarantees can not be given for straightforward syntax. Sometimes they rely on STL algorithms that are not very intuitive to use. Too many libraries roll their own which are unfortunately much more comfortable to use. Unless you have to combine them.
Variety of string representations
Now, this is a little bit of a platform problem - but I still hope it would have been better when a less obstinate standard string class would have been available earlier. The following string representations I use frequently:
generic LPCTSTR,
LPC(W)STR allocated by CoTaskMemAlloc,
BSTR, _bstr _t
(w)string,
CString,
std::vector
a roll-my-own class (sigh) that adds range checking and basic operations to a (w)char * buffer of known length
Build model.
I am sick to death of all the time spent muddling around with who-includes-what, forward declarations, optimizing precompiled headers and includes to keep at least incremental build times bearable, etc. It was great in the eighties, but now? There are so many hurdles to packing up a piece of code so it can be reused that even moms dog gets bored listening to me.
Hard to parse
This makes external tools especially hard to write, and get right. And today, we C++ guys are lacking mostly in the tool chain. I love my C# reflection and delegates but I can live without them. Without great refactoring, I can't.
Threading is too hard
Language doesn't even recognize it (by now), and the freedoms of the compiler - while great - are to painful.
Static and on-demand initialization
Technically, I cheat here: this is another puzzle piece in the "wrap up code for reuse": It's a nightmare to get something initialized only when it is needed. The best solution to all other redist problems is throwing everything into headers, this problem says "neeener - you cannot".
诚然,其中许多内容超出了严格的语言范围,但在我看来,整个工具链都需要进行判断和发展。