Bug: exec::repeat_effect fails to compile #1572
Description
I believe there is bug with exec::repeat_effect where using it when any sender results in a compilation failure. Root cause appears to be incorrect function call inside the implementation of repeat_effect_t::transform_sender in exec/repeat_effect_until.hpp. Line 242 calls operator() of repeat_effect_until_t{} with two arguments: a sender and a predicate. However, repeat_effect_until_t::operator() only provides overloads for zero arguments or a single sender argument.
Reproducible Example: https://godbolt.org/z/6434fGKcj
Proposed Patch:
diff --git a/include/exec/repeat_effect_until.hpp b/include/exec/repeat_effect_until.hpp
index c78922c7..72d42934 100644
--- a/include/exec/repeat_effect_until.hpp
+++ b/include/exec/repeat_effect_until.hpp
@@ -239,7 +239,7 @@ namespace exec {
auto transform_sender(_Sender &&__sndr, __ignore) {
return __sexpr_apply(
static_cast<_Sender &&>(__sndr), []<class _Child>(__ignore, __ignore, _Child __child) {
- return repeat_effect_until_t{}(stdexec::then(std::move(__child)), _never{});
+ return repeat_effect_until_t{}(stdexec::then(std::move(__child), _never{}));
});
}
};