https://github.com/N-Dekker created https://github.com/llvm/llvm-project/pull/117629
>From C++11, a conforming `size()` method is guaranteed to be a constant-time >function. `empty()` is not _generally_ more efficient than `size()`. It might >even be implemented in terms of `size()`. ---- Notes: - Microsoft's STL had implemented `empty()` as `return size() == 0`, until May 2021: https://github.com/microsoft/STL/pull/1836/files - The time complexity of `size()` (specifically for `std::set`) was discussed by the library working group in 2007-2009: https://cplusplus.github.io/LWG/issue632 >From 87688f9ec5e74f9b3c74df05a69a4f822966b5f1 Mon Sep 17 00:00:00 2001 From: Niels Dekker <n.dek...@lumc.nl> Date: Mon, 25 Nov 2024 21:48:57 +0100 Subject: [PATCH] [clang-tidy] Adjust size-empty doc because C++11 size() is constant-time >From C++11, a conforming `size()` method is guaranteed to be a constant-time >function. `empty()` is not _generally_ more efficient than `size()`. It might >even be implemented in terms of `size()`. --- .../clang-tidy/readability/ContainerSizeEmptyCheck.h | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/clang-tools-extra/clang-tidy/readability/ContainerSizeEmptyCheck.h b/clang-tools-extra/clang-tidy/readability/ContainerSizeEmptyCheck.h index 617dadce76bd3e..acd8a6bfc50f5e 100644 --- a/clang-tools-extra/clang-tidy/readability/ContainerSizeEmptyCheck.h +++ b/clang-tools-extra/clang-tidy/readability/ContainerSizeEmptyCheck.h @@ -18,12 +18,10 @@ namespace clang::tidy::readability { /// a call to `empty()`. /// /// The emptiness of a container should be checked using the `empty()` method -/// instead of the `size()` method. It is not guaranteed that `size()` is a -/// constant-time function, and it is generally more efficient and also shows -/// clearer intent to use `empty()`. Furthermore some containers may implement -/// the `empty()` method but not implement the `size()` method. Using `empty()` -/// whenever possible makes it easier to switch to another container in the -/// future. +/// instead of the `size()` method. It shows clearer intent to use `empty()`. +/// Furthermore some containers may implement the `empty()` method but not +/// implement the `size()` method. Using `empty()` whenever possible makes it +/// easier to switch to another container in the future. class ContainerSizeEmptyCheck : public ClangTidyCheck { public: ContainerSizeEmptyCheck(StringRef Name, ClangTidyContext *Context); _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
