From e0bbf5c87f621be233877217dd3e26770342c927 Mon Sep 17 00:00:00 2001
From: Vlad Zagorodniy <vladzzag@gmail.com>
Date: Sun, 1 Jul 2018 10:45:39 +0300
Subject: [PATCH] Use std::transform in libkwineffects implementation part

Summary:
Don't use raw loops, instead, use appropriate algorithm from STL to map
a list of toplevels to a list of EffectWindow.

Test Plan:
Tested Cover switch, Flip switch, Dialog parent, and Dim inactive effect.
They all still work.

Reviewers: #kwin, graesslin

Reviewed By: #kwin, graesslin

Subscribers: graesslin, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D13821
---
 effects.cpp | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/effects.cpp b/effects.cpp
index 266479548e..a3864a12ba 100644
--- a/effects.cpp
+++ b/effects.cpp
@@ -1078,10 +1078,12 @@ void EffectsHandlerImpl::setTabBoxDesktop(int desktop)
 EffectWindowList EffectsHandlerImpl::currentTabBoxWindowList() const
 {
 #ifdef KWIN_BUILD_TABBOX
-    EffectWindowList ret;
     const auto clients = TabBox::TabBox::self()->currentClientList();
-    for (auto c : clients)
-    ret.append(c->effectWindow());
+    EffectWindowList ret;
+    ret.reserve(clients.size());
+    std::transform(std::cbegin(clients), std::cend(clients),
+        std::back_inserter(ret),
+        [](auto client) { return client->effectWindow(); });
     return ret;
 #else
     return EffectWindowList();
@@ -1700,10 +1702,12 @@ template <typename T>
 EffectWindowList getMainWindows(Toplevel *toplevel)
 {
     T *c = static_cast<T*>(toplevel);
-    EffectWindowList ret;
     const auto mainclients = c->mainClients();
-    for (auto tmp : mainclients)
-        ret.append(tmp->effectWindow());
+    EffectWindowList ret;
+    ret.reserve(mainclients.size());
+    std::transform(std::cbegin(mainclients), std::cend(mainclients),
+        std::back_inserter(ret),
+        [](auto client) { return client->effectWindow(); });
     return ret;
 }
 
@@ -1818,9 +1822,12 @@ void EffectWindowImpl::unreferencePreviousWindowPixmap()
 
 EffectWindowList EffectWindowGroupImpl::members() const
 {
+    const auto memberList = group->members();
     EffectWindowList ret;
-    for (Toplevel * c : group->members())
-    ret.append(c->effectWindow());
+    ret.reserve(memberList.size());
+    std::transform(std::cbegin(memberList), std::cend(memberList),
+        std::back_inserter(ret),
+        [](auto toplevel) { return toplevel->effectWindow(); });
     return ret;
 }