examples

commit b7acadc829f6d835137fd72de76689db9c9a91e7
parent a792edfe4c25b783dd7d55c1cc547ee62b4c265f
Author: Henry Wilson <henry@henryandlizzy.uk>
Date:   Mon,  6 Feb 2023 21:54:43 +0000

coro-throwing: Test type that can handle throwing coroutine body

Diffstat:
M
.gitignore
 | 
1
+
A
src/coro-throwing.cpp
 | 
98
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

2 files changed, 99 insertions(+), 0 deletions(-)
diff --git a/.gitignore b/.gitignore
@@ -13,6 +13,7 @@
 /cobs
 /coro-poll
 /coro-round-robin
+/coro-throwing
 /coro-timer-dispatch
 /coro-unconditional-dispatch
 /crc-table
diff --git a/src/coro-throwing.cpp b/src/coro-throwing.cpp
@@ -0,0 +1,98 @@
+#include <coroutine>
+#include <iostream>
+#include <optional>
+#include <stdexcept>
+
+using namespace std;
+
+struct coroutine
+{
+	struct promise_type;
+	coroutine_handle<> h;
+	~coroutine()
+	{
+		if (not h.done())
+			h.destroy();
+	}
+};
+
+struct coroutine::promise_type
+{
+	coroutine get_return_object() noexcept { return {coroutine_handle<promise_type>::from_promise(*this)}; }
+	suspend_never initial_suspend() noexcept { return {}; }
+	suspend_always final_suspend() noexcept { return {}; }
+	void return_void() noexcept {}
+	void unhandled_exception() { throw; }
+};
+
+
+struct awaitable : suspend_always
+{
+	coroutine_handle<> suspended;
+	void await_suspend(coroutine_handle<> h)
+	{
+		suspended = h;
+	}
+} awaitable;
+
+coroutine no_throw()
+{
+	cerr << "no_throw()\n";
+	co_return;
+}
+
+
+coroutine initial_throw()
+{
+	cerr << "\ninitial_throw()\n";
+	throw runtime_error("initial_throw");
+	co_return;
+}
+
+coroutine resume_throw()
+{
+	cerr << "\nresume_throw()\n";
+	for (;;)
+	{
+		co_await awaitable;
+		cerr << "resume_throw() RESUMED\n";
+		throw runtime_error("resume_throw");
+	}
+}
+
+coroutine resume_nothrow()
+{
+	cerr << "\nresume_nothrow()\n";
+	for (;;)
+	{
+		co_await awaitable;
+		cerr << "resume_nothrow() RESUMED\n";
+	}
+}
+
+int main()
+{
+	try {
+		{
+			no_throw();
+		}
+		[[maybe_unused]] auto coro = initial_throw();
+	} catch (exception& e)
+	{
+		cerr << "Exception caught: " << e.what() << endl;
+	}
+
+	try {
+		{
+			[[maybe_unused]] auto coro = resume_nothrow();
+			cerr << "  suspend OK\n";
+			awaitable.suspended.resume();
+		}
+		[[maybe_unused]] auto coro = resume_throw();
+		cerr << "  suspend OK\n";
+		awaitable.suspended.resume();
+	} catch (exception& e)
+	{
+		cerr << "Exception caught: " << e.what() << endl;
+	}
+}