added support for coroutines

docs/src/cli.rst

@@ -8,19 +8,39 @@ You can register as many functions as you like with the `CLI` instance.
 
 .. code-block:: python
 
-   from targ import CLI
+    from targ import CLI
 
 
-   def add(a: int, b: int):
-      print(a + b)
+    def add(a: int, b: int):
+        print(a + b)
 
 
-   def subtract(a: int, b: int):
-      print(a - b)
+    def subtract(a: int, b: int):
+        print(a - b)
+
+
+    if __name__ == "__main__":
+        cli = CLI()
+        cli.register(add)
+        cli.register(subtract)
+        cli.run()
+
+You can also register coroutines, as well as normal functions:
+
+.. code-block:: python
+
+    import asyncio
+
+    from targ import CLI
+
+
+    async def timer(seconds: int):
+        print(f"Sleeping for {seconds}")
+        await asyncio.sleep(seconds)
+        print("Finished")
 
 
    if __name__ == "__main__":
       cli = CLI()
-      cli.register(add)
-      cli.register(subtract)
+      cli.register(timer)
       cli.run()

example_script.py

@@ -1,3 +1,5 @@
+import asyncio
+
 from targ import CLI
 
 
@@ -77,6 +79,18 @@ def create(username: str):
     print(f"Creating {username}")
 
 
+async def timer(seconds: int):
+    """
+    Countdown for a number of seconds.
+
+    :param seconds:
+        The number of seconds to countdown.
+    """
+    print(f"Sleeping for {seconds}")
+    await asyncio.sleep(seconds)
+    print("Finished")
+
+
 if __name__ == "__main__":
     cli = CLI()
     cli.register(say_hello)
@@ -85,4 +99,5 @@ def create(username: str):
     cli.register(print_pi)
     cli.register(compound_interest)
     cli.register(create, group_name="user")
+    cli.register(timer)
     cli.run()

targ/__init__.py

@@ -1,4 +1,5 @@
 from __future__ import annotations
+import asyncio
 from dataclasses import dataclass, field
 from functools import cached_property
 import inspect
@@ -160,7 +161,10 @@ def call_with(self, arg_class: Arguments):
             if callable(annotation):
                 kwargs[kwarg_key] = annotation(arg)
 
-        self.command(**kwargs)
+        if inspect.iscoroutinefunction(self.command):
+            asyncio.run(self.command(**kwargs))
+        else:
+            self.command(**kwargs)
 
 
 @dataclass