Better errors and return codes

Signed-off-by: Rahix <rahix@rahix.de>

README.md

@@ -130,6 +130,9 @@ print("Value: ", bc:get("some_noun"))
 ### `BaseControl:call(verb, ...)`
 Call a verb **asynchroneously**.  All parameters following `verb` will be given
 to the remote function.  There is no guarantee that the verb was actually run.
+`call` will return `true` if an attempt was made to run the verb and `false`
+otherwise.  `call` specifically does **not** error, because no guarantees
+could be made anyway.
 
 _Note_: For local verbs, the call will still be synchroneous.
 ```lua
@@ -146,8 +149,10 @@ bc:call("some_verb", "param_a_value", "param_b_value")
 ### `BaseControl:call_sync(verb, timeout, ...)`
 Call a verb **synchroneously**.  All parameters following `verb` will be given
 to the remote function.  `call_sync` will return the remote function's return
-value.  If timeout is not `nil` or `0`, `call_sync` will return early upon
+value.  If timeout is not `nil` or `0`, `call_sync` will error upon
 the timeout expiring.
+
+_Note_: For local verbs, the timeout can not be adhered to.
 ```lua
 local bc = require("bc")
 bc:register("stupid_add", function(a, b)

bc.lua

@@ -245,7 +245,7 @@ function BaseControl:get(noun, timeout)
       error("timeout")
     end
   else
-    return error("unknown")
+    return error("unknown noun \""..noun.."\"")
   end
 end
 
@@ -289,12 +289,16 @@ end
 function BaseControl:call(verb, ...)
   if self.local_verbs[verb] ~= nil then
     self.local_verbs[verb](...)
+    return true
   elseif self.remote_verbs[verb] ~= nil then
     self.network:send(self.remote_verbs[verb], {
       ty=Message.VerbRequest,
       verb=verb,
       param={...},
     })
+    return true
+  else
+    return false
   end
 end
 
@@ -320,7 +324,7 @@ function BaseControl:call_sync(verb, ...)
       error("timeout")
     end
   else
-    error("unknown")
+    error("unknown verb \""..verb.."\"")
   end
 end
 -- }}}