Set array size to known number of args

cmd/cmd.go

@@ -97,7 +97,7 @@ func New(cmd string) *Cmd {
 	utils.Check(err)
 
 	name := cmds[0]
-	args := make([]string, 0)
+	args := make([]string, len(cmds)-1)
 	for _, arg := range cmds[1:] {
 		args = append(args, arg)
 	}