Java

已检查的异常 类型擦除 缺少操作符重载(例如BigInteger/BigDecimal) 缺少regexp/date/duration /复杂文字 对不可变性的支持很差

Python

__init__ 有些库很笨拙，比如smtplib self必须在方法声明中!! (3.0之前)对unicode的支持有点差 缺少内联尝试捕获 没有直接引用"this"/current模块(相反必须使用sys.modules[__name__])

Python

Standard library disobeys their own style guidelines in many places. (PEP-8) Py3k's super keyword is full of unwanted magic (you can't assign it to a different name, works without self, why do we have this explicit parameter at all?) Unicode support is incomplete in Py2k and sucks in Py3k (standard input in unicode, no binary data! WTF? Creating a new WSGI standard is hacky.) The GIL. Very limited multi-threading support (with CPython) PyPI (Python Package Index) sucks. Envious glance at rubygems

Perl 5:

All the really good stuff nowadays seems to require mod_perl, which has low availability everywhere I want to go. Some really incredible functionality can be encapsulated in modules, but what is under the hood is often fragile or frightening: source filters, typeglobs, whatever Moose is doing... DateTime is brilliant but still made some very bad design decisions (not returning a stopwatch duration when subtracting two DateTime objects) Dual-lifed modules in core and on CPAN still cause conflicts module authors still put interactive stuff in their module configuration scripts so that they can't be automatically installed

Lua

我喜欢用Lua编程，但下面是让我头疼的事情:

没有办法用这种语言编写API——不像C .h文件或Java接口 语言有一流的功能，但有人忘记告诉设计库的人。 编写函数的语法太重量级了。 语法分为语句和表达式。 表达式形式是贫乏的:没有let形式，没有真正的条件表达式，……

尽管如此，我还是坚持认为Lua非常棒:-)

C++

The inconsistencies in the libraries related to char* and std::string. All C++ libs should take std::strings. Characters are not bytes with respect to iostream. I do a lot of byte-oriented work. Having a "byte" type and a "character" type would significantly make it simpler. That, too, would permit scaling to Unicode somewhat easier. Bit operations should be easy on a value. I should be able to access and set the n'th bit of a value without playing AND/OR dancing. The lack of a standardized interface for GUIs. This is where Microsoft has really been able to position themselves well with C#. A standard interface binding that OS makers provide would go really far for my work.