参考资料：
ubuntu安装llvm，含clang：https://apt.llvm.org/
clang ast-dump cli:
clang -Xclang -ast-dump -fsyntax-only -Xclang -ast-dump-filter -Xclang FaceDetector::FaceDetector -I/path/to/opencv-4.5.5/include/opencv4/ xxx.hpp
clang重命名类的Cursor：
- CursorKind.NAMESPACE_ALIAS
- CursorKind.TYPE_ALIAS_DECL
- CursorKind.TYPE_ALIAS_TEMPLATE_DECL
clang ElaboratedType
- Represents a type that was referred to using an elaborated type keyword, e.g., struct S, or via a qualified name, e.g., N::M::type, or both.
- This type is used to keep track of a type name as written in the source code, including tag keywords and any nested-name-specifiers. The type itself is always "sugar", used to express what was written in the source code but containing no additional semantic information.
CMake file API：用于获取JSON格式的语义信息
mkdir build
cd build/
mkdir -p .cmake/api/v1/query
touch .cmake/api/v1/query/codemodel-v2 # 支持cache-v2、cmakeFiles-v1、toolchains-v1
cmake .. -DCMAKE_BUILD_TYPE=Release -G "CodeBlocks - Unix Makefiles"
ls .cmake/api/v1/reply
clang get_usr
get_usr中各种符号含义：
- @N@: Namespace
- @E@: Enum
- @F@: Function
- @S@: Struct
例如：
"c:@N@cv@ST>1#T@Ptr"：cv::Ptr<T>
"c:@N@cv@E@WindowFlags@WINDOW_OPENGL"：cv::WindowFlags.WINDOW_OPENGL
"c:@N@cv@N@cuda@S@GpuMat@F@GpuMat#*$@N@cv@N@cuda@S@GpuMat@S@Allocator#"：cv::cuda::CpuMat::GptMat
"c:@N@cv@S@Ptr>#$@N@cv@N@cudacodec@S@VideoReader@F@operator->#1"：cv::Ptr<cv::cudacodec::VideoReader>
usr字符串解析：
nsc = re.findall(r'(?:@[NSE]@\w+){1,1000}', usr[:index])
# nss = ['::'.join(x[3:].split('@N@')) for x in nsc]
nss = [x[3:].replace('@N@', '::').replace('@S@', '::').replace('@E@', '::') for x in nsc]
