Python:

缺少静态类型 默认参数处理(特别是可以为未来的调用者更改默认参数的事实!) 需要的下划线太多(构造函数必须调用__init__) 缺少适当的私有成员和函数(惯例只是说大多数以下划线开头的东西都是私有的，除了像__getattr__这样的东西不是) 有趣的打印到文件的语法(但他们在Python 3中修复了这个问题)

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... :)

c++缺乏好的重构工具，缺乏受控异常

Java缺少模板，缺少const关键字

Lua

If you do foo.bar(1,2) then 'self' is nil inside the bar method. You must remember to do foo:bar(1,2) instead. I'd rather have that switched ('self' should be defined by default unless you use the ':' operator, or you call a function that isn't a method). Variables are global by default. I'd rather ditch the 'local' keyword and have a 'global' one instead. Undeclared variables are assigned the nil. I'd rather receive an error message. You can sidestep this by manipulating the global env's metatable, but I'd rather have it implemented by default and be able to deactivate it. Multiple returned values on parameters are not handled very nicely. Say you have a function foo() that returns 1,2,3 (three values) and bar() returns 4,5 (two values). If you do print(foo(),bar()) you will get "1,4,5" ... only the "last" tuple is expanded on calls. The # (table length) operator only works in tables indexed with continuous integers. If your table isn't like that and you want to know how many elements does it have, you need to either parse it with a loop, or update a counter each time you insert/remove an element from it.

按最讨厌到最不讨厌的顺序排列。

1.) Backwards compatibility police. Yes backcompat is a strength but Perl 5 takes it too far. Now we don't really even get new features in our language without having to enable them explicitly. I'm much prefer the inverse, if a new feature causes a problem let me disable it or enforce old behavior. e.g. perl 5.10 added say I'd rather have no feature 'say' if I have my own say implemented than have to put use feature 'say'; or use 5.010; also if 5.8 worked but 5.10 didn't. I'd rather have use 5.008; to restrict my code to only use features available up to and including 5.8 if no use version; was defined then it should be defaulted to whatever version you're running, and a recommended practice of not to restrict it unless you have to.

2)。过度的样板。

#!/usr/bin/perl
use strict;
use warnings;
use utf8;
use autodie;
use English '-no_match_vars';
use 5.010;
package Package::Name;

BEGIN {
    Package::Name::VERSION = 0.1;
}

sub somesub {
    my $self = shift;
    my ( $param1, $param2 ) = @_;
}
1;

现在你可以开始编码了。这不会因为第一条而改变。当然也有一些捷径，比如使用common::sense;或者使用modern::perl;这将缩短上面的内容，你可能需要一些稍微不同的模块或pragma。但因为第一条，我们永远无法把它降低到。

#!/usr/bin/perl
package Package::Name 0.01;

sub somesub ( $param1, $param2 ) {
}

一些模块正在帮助这一点，在5.0.12中有新的包版本，它完全允许这种语法，尽管我认为它需要使用5.012;首先，和Method::签名，但它永远不会完全解决，(在语言)。

3)。糟糕的变量选择

吸吸文件

#!/usr/bin/perl
use strict;
use warnings;
open my $fh, "< foo" or die $!;
local $/; # enable localized slurp mode
my $content = <$fh>;
close $fh;

WTF是$!和美元/ ?重写为易读。

#!/usr/bin/perl
use strict;
use warnings;
use English '-no_match_vars';
open my $fh, "< foo" or die $ERRNO;
local $INPUT_RECORD_SEPARATOR; # enable localized slurp mode
my $content = <$fh>;
close $fh;

不要忘记，如果您不想受到性能影响，'-no_match_vars'必须存在。

不直接创建匿名标量怎么样?

#!/usr/bin/perl
my $scalar_ref = \do{ my $anon_scalar };

他们就不能想出点什么办法吗?

#!/usr/bin/perl
my $scalar_ref = <>;

哦，perl是线程不友好的，因为所有的变量(包括特殊的变量)默认是全局的。至少现在你可以使用我的$_;对其词法作用域，并对其他词使用local。

4.)非常难看的语法

MooseX::Declare是一个更好的语法。我也希望->被替换为。(个人喜好不太重要)

5)。太多的TIMTOWTDI或太多的最佳实践似乎你必须读3-5本书才能弄清楚你应该如何做事情。

6)。以前的(不再适用)。Un-sane版本。5.10.0有新功能5.10.1的新功能没有设定时间，直到下一个版本。现在是每年一次的特性发布，每季度更新一次。

7)。象牙塔视角。社区问题，似乎是许多开发者想要设置更高的准入门槛，并认为可以不尊重n00b(或任何不同意他们的人)。

8)。疯狂的版本号/字符串Perl有浮点版本号，它们很难看。开发人员不知道并不是所有的下游处理版本比较的方式都是一样的。不是语言问题

0.012 # simple
5.012001 # semantic 
4.101900 # time based + version (for multiple versions in a day)
0.035_002 # prerelease

所有有效版本的perl..我们就不能用…

0.12 # simple
5.12.1 # semantic
20100713 # time based (just use the date and be careful not to need to release more than 1 a day)
0.35-beta2 # prerelease

除了

9)。升级后没有明显的方法重新安装所有XS模块

Python

没有名称空间。 伪私有属性/名称混淆(主要使用getattr)。 文件路径操作分布在多个模块中。串在一起的os。路径调用是丑陋的，难以读取，并且在大多数情况下违反了DRY。常见的文件路径操作仍然没有方便的函数，比如获取目录下的文件列表。修复此问题的路径类型模块被拒绝。

([f for f in os.listdir('/file/path') if os.path.isfile(os.path. isfile)加入(/文件/路径,f))))

Python文档(我非常、非常、非常感谢有文档，而且它的格式很好，但我讨厌费力地在5000行快速入门使用示例中找到特定模块的单个函数文档(我正在查看optparse和logging))。内置类型在近10个不同的地方被零碎地记录。