C

It's so flexible and powerful that it's really easy to write really awful, or downright dangerous code (or, if you prefer, "with great power comes great responsibility"). '=' for assignment, and '==' for equality; easy to confuse in 'if' statements. The implementation of a number of fundamental parts of the language are compiler-dependent; e.g. the size of the basic types, order of bits in bitfields, padding and byte order in unions. Bitfields aren't parameterisable (i.e. you can array of ints, but you can't have an array of bits). String handling could be improved.

JavaScript:

All the coolest things are insanely complex, but then, all the coolness is also wrapped up in such a small amount of code that you feel stupid for struggling to follow it '+' is an absurd choice of operator for concatenation in a weakly-typed language. Were they trying to scare off the noobs? It's a cross-browser compatibility minefield (never mind if it's even turned on or not) It's generally untrusted - associated with scummery such as blocking the back button, pop-ups that never die, etc. It's nearly impossible to debug because there are only a few different error messages and a few different types (Number, String, Object, etc.)

如果不是jQuery，我可能还是会像以前一样讨厌它:)

Perl代表了一种可怕的语言。

No "public" or "private" or "protected" declarations/definitions. The "my $variable_name;" does not declare a global outside of a subroutine. The "my $variable_name;" gets accessed by subroutines but "use strict;" or other "use " creates warnings. Function prototypes end up unexplained, undemonstrated, unwanted, or some other excuse. Overzealous symbol use ends up "cool and quick" when reading globs of symbols. When one gets hot they like to stay hot, and need nothing to cool them. After a week of Perl, I end up unable to write a function and prototype it. What exactly is a module and does it actually NEED a ".pm" extension? If you want to create a public variable and access it from inside a subroutine, how do you accomplish this without creating a warning? Where do you find some neat scripts that teach one some neat Perl?

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。

Haskell:

空间泄漏——懒惰的默认代价——也许代价太高了? 甚至像head和tail这样的纯函数也会调用错误并引导您进入IO。 fail from Monad -带回MonadZero。 Num类-(+)应该在AdditiveGroup或类似的类型中。 那个单子不是一个应用程序。

Python

No statements in lambdas. GRRRR foo( a for b in c if d ) feels wrong, it surprises me every time I get away with it. Shouldin't it be foo( (a for b in c if d) )? Can i have a dict comprehension? map and filter operators have special syntax in list comprehensions, how about something for reduce? or sort? Just by having a yield statement in it, a function is magically transformed into a generator, and its interface changes completely. Also, that generator cannot do any work before the first next(). at least, not without using a function that returns a generator.

JavaScript

No brief syntax for making modular code libraries. You have to call a function that returns a dictionary of public methods. And you have to edit that in (at least) two places every time you alter the interface of your module. Creating closures involves returning it from a function that returns a function from ('sup dog) yo' function. Clutter! for each ( foo ) syntax and behavior feels like an afterthought. Knowing when your code will actually run (and in what order) is more of a dark-art. The only way to get it right for sure is put everything (yes, that too) in one big file. and even then you still need to wait for a document.onload Am i missing something? is there no trivial way to get json serialized values without building them by hand? (yes jQuery can do this, sort of).