diff options
author | Dan Goodliffe <dan@randomdan.homeip.net> | 2022-12-28 13:49:54 +0000 |
---|---|---|
committer | Dan Goodliffe <dan@randomdan.homeip.net> | 2022-12-28 13:50:06 +0000 |
commit | 69acdf6584be2a04094e27b395c50c071b2b15cf (patch) | |
tree | b9134ccb2087960637c6d7059f51af7fb02c18e3 /lib | |
parent | No need for the range hack, the shadow box is just centred around the origin (diff) | |
download | ilt-69acdf6584be2a04094e27b395c50c071b2b15cf.tar.bz2 ilt-69acdf6584be2a04094e27b395c50c071b2b15cf.tar.xz ilt-69acdf6584be2a04094e27b395c50c071b2b15cf.zip |
Use the existence of .substr(...) to test if a T is stringlike
Diffstat (limited to 'lib')
-rw-r--r-- | lib/stream_support.cpp | 11 | ||||
-rw-r--r-- | lib/stream_support.hpp | 6 |
2 files changed, 4 insertions, 13 deletions
diff --git a/lib/stream_support.cpp b/lib/stream_support.cpp deleted file mode 100644 index 2054873..0000000 --- a/lib/stream_support.cpp +++ /dev/null @@ -1,11 +0,0 @@ -#include "stream_support.hpp" - -#include <array> -#include <vector> - -static_assert(spanable<std::vector<int>>); -// static_assert(spanable<std::vector<char>>); -static_assert(spanable<std::array<int, 1>>); -// static_assert(spanable<std::array<char, 1>>); -static_assert(!spanable<std::string>); -static_assert(!spanable<std::string_view>); diff --git a/lib/stream_support.hpp b/lib/stream_support.hpp index 5f45cbf..a3565d8 100644 --- a/lib/stream_support.hpp +++ b/lib/stream_support.hpp @@ -8,14 +8,16 @@ #include <sstream> #include <type_traits> +template<typename S> +concept stringlike = requires(const S & s) { s.substr(0); }; template<typename T> concept spanable = std::is_constructible_v<std::span<const typename T::value_type>, T> && ! -std::is_same_v<char, std::decay_t<typename T::value_type>>; +stringlike<T> && !std::is_same_v<std::span<typename T::value_type>, T>; namespace std { template<typename T, std::size_t L> std::ostream & - operator<<(std::ostream & s, const span<const T, L> v) + operator<<(std::ostream & s, const span<T, L> v) { s << '('; for (const auto & i : v) { |