René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Highlight C++11+ attribute specifications","articleBody":"I have for the time being implemented this in my own local copy (in ~/.vim/syntax). I am not an expert at vim syntax files, so I have one minor problem which is that if you have `[noreturn]`, the `noreturn` will be highlighted (and some other weird edge cases), but I'm not able to fix this myself, so I've simply attached attached my diff so far:\r\n\r\n```diff\r\ndiff --git a/usr/local/share/nvim/runtime/syntax/cpp.vim b/home/cactus/.vim/syntax/cpp.vim\r\nindex ed38913..92fd735 100644\r\n--- a/usr/local/share/nvim/runtime/syntax/cpp.vim\r\n+++ b/home/cactus/.vim/syntax/cpp.vim\r\n@@ -47,6 +47,8 @@ if !exists(\"cpp_no_cpp11\")\r\n   syn region cppRawString\tmatchgroup=cppRawStringDelimiter start=+\\%(u8\\|[uLU]\\)\\=R\"\\z([[:alnum:]_{}[\\]#\u003c\u003e%:;.?*\\+\\-/\\^\u0026|~!=,\"']\\{,16}\\)(+ end=+)\\z1\"+ contains=@Spell\r\n   syn match cppCast\t\t\"\\\u003c\\(const\\|static\\|dynamic\\)_pointer_cast\\s*\u003c\"me=e-1\r\n   syn match cppCast\t\t\"\\\u003c\\(const\\|static\\|dynamic\\)_pointer_cast\\s*$\"\r\n+  syn region cppAttrSpec\tmatchgroup=cppAttributeDelimiter start=+\\[\\[+ end=+\\]\\]+ contains=TOP\r\n+  syn keyword cppAttribute\tnoreturn carries_dependency contained containedin=cppAttrSpec\r\n endif\r\n \r\n \" C++ 14 extensions\r\n@@ -56,6 +58,7 @@ if !exists(\"cpp_no_cpp14\")\r\n   syn match cppNumber\t\tdisplay \"\\\u003c[1-9]\\('\\=\\d\\+\\)*\\(u\\=l\\{0,2}\\|ll\\=u\\)\\\u003e\" contains=cFloat\r\n   syn match cppNumber\t\tdisplay \"\\\u003c0x\\x\\('\\=\\x\\+\\)*\\(u\\=l\\{0,2}\\|ll\\=u\\)\\\u003e\"\r\n   syn case match\r\n+  syn keyword cppAttribute\tdeprecated contained containedin=cppAttrSpec\r\n endif\r\n \r\n \" C++ 20 extensions\r\n@@ -65,12 +68,14 @@ if !exists(\"cpp_no_cpp20\")\r\n   syn keyword cppStructure\tconcept\r\n   syn keyword cppType\t\tchar8_t\r\n   syn keyword cppModule\t\timport module export\r\n+  syn keyword cppAttribute\tlikely unlikely no_unique_address contained containedin=cppAttrSpec\r\n endif\r\n \r\n \" C++ 17 extensions\r\n if !exists(\"cpp_no_cpp17\")\r\n   syn match cppCast\t\t\"\\\u003creinterpret_pointer_cast\\s*\u003c\"me=e-1\r\n   syn match cppCast\t\t\"\\\u003creinterpret_pointer_cast\\s*$\"\r\n+  syn keyword cppAttribute\tfallthrough nodiscard maybe_unused contained containedin=cppAttrSpec\r\n endif\r\n \r\n \" The minimum and maximum operators in GNU C++\r\n@@ -90,6 +95,8 @@ hi def link cppBoolean\t\tBoolean\r\n hi def link cppConstant\t\tConstant\r\n hi def link cppRawStringDelimiter\tDelimiter\r\n hi def link cppRawString\t\tString\r\n+hi def link cppAttributeDelimiter\tStorageClass\r\n+hi def link cppAttribute\tStorageClass\r\n hi def link cppNumber\t\tNumber\r\n hi def link cppModule\t\tInclude\r\n```\r\n\r\nI have made an effort to not highlight attributes outside of valid contexts (e.g. `likely` is not highlighted unless it's inside an attribute specifier), but it seems to have some unfortunate side effects. At the moment, this is the resulting highlighting in a few cases:\r\n![image](https://user-images.githubusercontent.com/3360049/126176186-a2ea0408-15d6-4775-8fef-d82a22820813.png)\r\n","author":{"url":"https://github.com/sophec","@type":"Person","name":"sophec"},"datePublished":"2021-07-19T14:25:03.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/57/vim-cpp/issues/57"}