util.promise: Switch order of parameters to join()

This saves awkward fiddlery with varargs and also echoes the
signature of pcall/xpcall.

1 files changed, 2 insertions, 4 deletions

diff --git a/util/promise.lua b/util/promise.lua
index 89bd1f26..ea30898c 100644
--- a/util/promise.lua
+++ b/util/promise.lua
@@ -146,12 +146,10 @@ local function all_settled(promises)
 	end);
 end
 
-local function join(...)
+local function join(handler, ...)
 	local promises, n = { ... }, select("#", ...);
-	local handler = promises[n];
-	promises[n] = nil;
 	return all(promises):next(function (results)
-		return handler(unpack(results, 1, n - 1));
+		return handler(unpack(results, 1, n));
 	end);
 end