From 1c9242bab22f781a734cff1cb9e61e5e8661749e Mon Sep 17 00:00:00 2001
From: hjk <hjk@qt.io>
Date: Tue, 4 Jun 2024 11:13:36 +0200
Subject: [PATCH] LayoutBuilder: Potentially save a few cycles

... by not actually creating the unused instances of the Id types.

Change-Id: I6955046fa1b457ea70d36090d3bf0051b31dfdaa
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>
---
 tests/manual/layoutbuilder/v2/lb.h | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/tests/manual/layoutbuilder/v2/lb.h b/tests/manual/layoutbuilder/v2/lb.h
index 99c87af564b..cdccc858701 100644
--- a/tests/manual/layoutbuilder/v2/lb.h
+++ b/tests/manual/layoutbuilder/v2/lb.h
@@ -43,13 +43,12 @@ namespace Layouting {
 
 class NestId {};
 
-template <typename T1, typename T2>
+template <typename Id, typename Arg>
 class IdAndArg
 {
 public:
-    IdAndArg(const T1 &id, const T2 &arg) : id(id), arg(arg) {}
-    const T1 id;
-    const T2 arg; // FIXME: Could be const &, but this would currently break bindTo().
+    IdAndArg(Id, const Arg &arg) : arg(arg) {}
+    const Arg arg; // FIXME: Could be const &, but this would currently break bindTo().
 };
 
 // The main dispatcher
@@ -70,7 +69,7 @@ public:
     template <typename Id, typename Arg>
     BuilderItem(IdAndArg<Id, Arg> && idarg)
     {
-        apply = [&idarg](X *x) { doit(x, idarg.id, idarg.arg); };
+        apply = [&idarg](X *x) { doit(x, Id{}, idarg.arg); };
     }
 
     std::function<void(X *)> apply;