# HG changeset patch
# User Matthew Wild <mwild1@gmail.com>
# Date 1602444332 -3600
# Node ID 89162d27e1b1064e465d7211bbeacfcdda2386e3
# Parent  498b3ab49b9cd4cb38a65d6111a15771f1cc201a
util.startup: Handle missing nparams field from debug info (not present in 5.1)

diff -r 498b3ab49b9c -r 89162d27e1b1 util/startup.lua
--- a/util/startup.lua	Sun Oct 11 14:27:28 2020 +0200
+++ b/util/startup.lua	Sun Oct 11 20:25:32 2020 +0100
@@ -198,11 +198,12 @@
 	end
 	function mt.__tostring(f)
 		local info = debug.getinfo(f, "Su");
-		for i = 1, info.nparams do
+		local n_params = info.nparams or 0;
+		for i = 1, n_params do
 			info[i] = debug.getlocal(f, i);
 		end
 		if info.isvararg then
-			info[info.nparams+1] = "...";
+			info[n_params+1] = "...";
 		end
 		return ("function<%s:%d>(%s)"):format(info.short_src:match("[^\\/]*$"), info.linedefined, table.concat(info, ", "));
 	end