1 files changed, 67 insertions, 0 deletions
diff --git a/examples/coroutines/coroutines.tm b/examples/coroutines/coroutines.tm
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+++ b/examples/coroutines/coroutines.tm
@@ -0,0 +1,67 @@
+# This is a coroutine library that uses libaco (https://libaco.org)
+#
+# Lua programmers will recognize this as similar to Lua's stackful coroutines.
+#
+# Async/Await programmers will weep at its beauty and gnash their teeth and
+# rend their garments in despair at what they could have had.
+
+use ./aco.h
+use ./aco.c
+use ./acoyield.S
+
+func main()
+    say("Example usage")
+    co := Coroutine(func()
+        say("I'm in the coroutine!")
+        yield()
+        say("I'm back in the coroutine!")
+    )
+    >> co
+    say("I'm in the main func")
+    >> co.resume()
+    say("I'm back in the main func")
+    >> co.resume()
+    say("I'm back in the main func again")
+    >> co.resume()
+
+struct aco_t(; extern, opaque)
+struct aco_shared_stack_t(; extern, opaque)
+
+_main_co : @aco_t? = none
+_shared_stack : @aco_shared_stack_t? = none
+
+struct Coroutine(co:@aco_t)
+    convert(fn:func() -> Coroutine)
+        if not _main_co
+            _init()
+
+        main_co := _main_co
+        shared_stack := _shared_stack
+        aco_ptr := C_code:@aco_t(
+            aco_create(@main_co, @shared_stack, 0, (void*)@fn.fn, @fn.userdata)
+        )
+        return Coroutine(aco_ptr)
+
+    func is_finished(co:Coroutine->Bool; inline)
+        return C_code:Bool(((aco_t*)@co.co)->is_finished)
+
+    func resume(co:Coroutine->Bool)
+        if co.is_finished()
+            return no
+        C_code { aco_resume(@co.co); }
+        return yes
+
+func _init()
+    C_code {
+        aco_set_allocator(GC_malloc, NULL);
+        aco_thread_init(aco_exit_fn);
+    }
+    _main_co = C_code:@aco_t(aco_create(NULL, NULL, 0, NULL, NULL))
+
+    _shared_stack = C_code:@aco_shared_stack_t(aco_shared_stack_new(0))
+
+func yield(; inline)
+    C_code {
+        aco_yield();
+    }
+