ios - #pragma objective-c : can you have more than just 'mark' ?

Question

我熟悉 #pragma mark objective-c/xcode/ios 开发，它对于查找代码段很有用。

但是，我想知道除了'mark'之外是否还有其他关键字。比如，你能做#pragma somethingelse吗？提前致谢!

Answer 1

首先，举几个例子:

1. 您可以控制诊断:

   http://clang.llvm.org/docs/UsersManual.html#controlling-diagnostics-via-pragmas

2. 来自同一个链接:

   • clang supports the Microsoft "#pragma pack" feature for controlling record layout. GCC also contains support for this feature, however where MSVC and GCC are incompatible clang follows the MSVC definition.

   • clang supports the Microsoft #pragma comment(lib, "foo.lib") feature for automatically linking against the specified library. Currently this feature only works with the Visual C++ linker.

   • clang supports the Microsoft #pragma comment(linker, "/flag:foo") feature for adding linker flags to COFF object files. The user is responsible for ensuring that the linker understands the flags.

   不过，该列表中的第二个和第三个不适用于您的 iOS 代码。

3. 维基百科 [ link ] 表示 clang 也支持 #pragma once。

最后，这是一个指向 clang API documentation 的链接pragma 处理代码。您可以从那里浏览以查看其他所有内容。特别是，TokenKinds.def 描述了所有接受的 token ，因此大概是完整的:

#pragma unused
#pragma GCC visibility [push/pop]
#pragma pack [value/show/push/pop/etc/etc/etc]
#pragma clang __debug parser_crash
#pragma clang __debug captured
#pragma ms_struct [on/off]
#pragma align [native/natural/mac68k/power/reset]
#pragma weak [identifier]
#pragma weak [identifier = identifier] // alias
#pragma redefine_extname [identifier identifier]
#pragma STDC FP_CONTRACT
#pragma OPENCL EXTENSION
#pragma omp [...]
#pragma detect_mismatch
#pragma comment

解析代码，在ParsePragma.cpp中找到, 似乎表明并非所有这些都已实现，即使前端接受了它们也是如此。