use structured binding declarations

Shorter.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

15 files changed, 49 insertions, 61 deletions

diff --git a/src/RemoteTagCache.cxx b/src/RemoteTagCache.cxx
index 3377a5831..facf6300d 100644
--- a/src/RemoteTagCache.cxx
+++ b/src/RemoteTagCache.cxx
@@ -42,9 +42,9 @@ RemoteTagCache::Lookup(const std::string &uri) noexcept
 	std::unique_lock<Mutex> lock(mutex);
 
 	KeyMap::insert_commit_data hint;
-	auto result = map.insert_check(uri, Item::Hash(), Item::Equal(), hint);
-	if (result.second) {
-		auto *item = new Item(*this, uri);
+	auto [tag, value] = map.insert_check(uri, Item::Hash(), Item::Equal(), hint);
+	if (value) {
+		auto item = new Item(*this, uri);
 		map.insert_commit(*item, hint);
 		waiting_list.push_back(*item);
 		lock.unlock();
@@ -70,15 +70,13 @@ RemoteTagCache::Lookup(const std::string &uri) noexcept
 			ItemResolved(*item);
 			return;
 		}
-	} else if (result.first->scanner) {
+	} else if (tag->scanner) {
 		/* already scanning this one - no-op */
 	} else {
 		/* already finished: re-invoke the handler */
 
-		auto &item = *result.first;
-
-		idle_list.erase(waiting_list.iterator_to(item));
-		invoke_list.push_back(item);
+		idle_list.erase(waiting_list.iterator_to(*tag));
+		invoke_list.push_back(*tag);
 
 		ScheduleInvokeHandlers();
 	}
diff --git a/src/client/Subscribe.cxx b/src/client/Subscribe.cxx
index 0b65d5b1b..dcfa81408 100644
--- a/src/client/Subscribe.cxx
+++ b/src/client/Subscribe.cxx
@@ -34,8 +34,7 @@ Client::Subscribe(const char *channel) noexcept
 	if (num_subscriptions >= MAX_SUBSCRIPTIONS)
 		return Client::SubscribeResult::FULL;
 
-	auto r = subscriptions.insert(channel);
-	if (!r.second)
+	if (!subscriptions.insert(channel).second)
 		return Client::SubscribeResult::ALREADY;
 
 	++num_subscriptions;
diff --git a/src/db/Count.cxx b/src/db/Count.cxx
index 68ee99c11..2df72e1e1 100644
--- a/src/db/Count.cxx
+++ b/src/db/Count.cxx
@@ -57,9 +57,9 @@ Print(Response &r, TagType group, const TagCountMap &m) noexcept
 {
 	assert(unsigned(group) < TAG_NUM_OF_ITEM_TYPES);
 
-	for (const auto &i : m) {
-		tag_print(r, group, i.first.c_str());
-		PrintSearchStats(r, i.second);
+	for (const auto &[tag, stats] : m) {
+		tag_print(r, group, tag.c_str());
+		PrintSearchStats(r, stats);
 	}
 }
 
@@ -68,8 +68,7 @@ stats_visitor_song(SearchStats &stats, const LightSong &song) noexcept
 {
 	stats.n_songs++;
 
-	const auto duration = song.GetDuration();
-	if (!duration.IsNegative())
+	if (const auto duration = song.GetDuration(); !duration.IsNegative())
 		stats.total_duration += duration;
 }
 
@@ -77,8 +76,7 @@ static void
 CollectGroupCounts(TagCountMap &map, const Tag &tag,
 		   const char *value) noexcept
 {
-	auto r = map.insert(std::make_pair(value, SearchStats()));
-	SearchStats &s = r.first->second;
+	auto &s = map.insert(std::make_pair(value, SearchStats())).first->second;
 	++s.n_songs;
 	if (!tag.duration.IsNegative())
 		s.total_duration += tag.duration;
diff --git a/src/db/DatabasePrint.cxx b/src/db/DatabasePrint.cxx
index b4d9315a2..a5fae49fe 100644
--- a/src/db/DatabasePrint.cxx
+++ b/src/db/DatabasePrint.cxx
@@ -195,11 +195,11 @@ PrintUniqueTags(Response &r, ConstBuffer<TagType> tag_types,
 	const char *const name = tag_item_names[tag_types.front()];
 	tag_types.pop_front();
 
-	for (const auto &i : map) {
-		r.Format("%s: %s\n", name, i.first.c_str());
+	for (const auto &[key, tag] : map) {
+		r.Format("%s: %s\n", name, key.c_str());
 
 		if (!tag_types.empty())
-			PrintUniqueTags(r, tag_types, i.second);
+			PrintUniqueTags(r, tag_types, tag);
 	}
 }
 
diff --git a/src/db/plugins/simple/Directory.cxx b/src/db/plugins/simple/Directory.cxx
index e78b6e6fb..8710b4f1c 100644
--- a/src/db/plugins/simple/Directory.cxx
+++ b/src/db/plugins/simple/Directory.cxx
@@ -138,13 +138,10 @@ Directory::LookupDirectory(std::string_view _uri) noexcept
 
 	Directory *d = this;
 	do {
-		auto s = uri.Split(PathTraitsUTF8::SEPARATOR);
-		if (s.first.empty())
+		auto [name, rest] = uri.Split(PathTraitsUTF8::SEPARATOR);
+		if (name.empty())
 			break;
 
-		const auto name = s.first;
-		const auto rest = s.second;
-
 		Directory *tmp = d->FindChild(name);
 		if (tmp == nullptr)
 			/* not found */
diff --git a/src/db/update/Walk.cxx b/src/db/update/Walk.cxx
index 3e0677e91..43366067a 100644
--- a/src/db/update/Walk.cxx
+++ b/src/db/update/Walk.cxx
@@ -427,21 +427,19 @@ UpdateWalk::DirectoryMakeUriParentChecked(Directory &root,
 	StringView uri(_uri);
 
 	while (true) {
-		auto s = uri.Split('/');
-		const std::string_view name = s.first;
-		const auto rest = s.second;
+		auto [name, rest] = uri.Split('/');
 		if (rest == nullptr)
 			break;
 
 		if (!name.empty()) {
 			directory = DirectoryMakeChildChecked(*directory,
 							      std::string(name).c_str(),
-							      s.first);
+							      name);
 			if (directory == nullptr)
 				break;
 		}
 
-		uri = s.second;
+		uri = rest;
 	}
 
 	return directory;
diff --git a/src/event/WinSelectBackend.cxx b/src/event/WinSelectBackend.cxx
index e8d7ab12d..67a574992 100644
--- a/src/event/WinSelectBackend.cxx
+++ b/src/event/WinSelectBackend.cxx
@@ -156,10 +156,10 @@ WinSelectBackend::ReadEvents(int timeout_ms) noexcept
 	for (const auto i : except_set)
 		items[i].events |= WinSelectEvents::WRITE;
 
-	for (auto &i : items)
-		if (i.second.events != 0) {
-			result.Add(i.second.events, i.second.obj);
-			i.second.events = 0;
+	for (auto &[key, item] : items)
+		if (item.events != 0) {
+			result.Add(item.events, item.obj);
+			item.events = 0;
 		}
 
 	return result;
diff --git a/src/input/plugins/CurlInputPlugin.cxx b/src/input/plugins/CurlInputPlugin.cxx
index 3cdab5653..057f7cd9b 100644
--- a/src/input/plugins/CurlInputPlugin.cxx
+++ b/src/input/plugins/CurlInputPlugin.cxx
@@ -395,8 +395,8 @@ CurlInputStream::CurlInputStream(EventLoop &event_loop, const char *_url,
 {
 	request_headers.Append("Icy-Metadata: 1");
 
-	for (const auto &i : headers)
-		request_headers.Append((i.first + ":" + i.second).c_str());
+	for (const auto &[key, header] : headers)
+		request_headers.Append((key + ":" + header).c_str());
 }
 
 CurlInputStream::~CurlInputStream() noexcept
diff --git a/src/input/plugins/QobuzClient.cxx b/src/input/plugins/QobuzClient.cxx
index bfffd863a..7655737f7 100644
--- a/src/input/plugins/QobuzClient.cxx
+++ b/src/input/plugins/QobuzClient.cxx
@@ -174,8 +174,8 @@ QobuzClient::MakeUrl(const char *object, const char *method,
 	uri += method;
 
 	QueryStringBuilder q;
-	for (const auto &i : query)
-		q(uri, i.first.c_str(), i.second.c_str());
+	for (const auto &[key, url] : query)
+		q(uri, key.c_str(), url.c_str());
 
 	q(uri, "app_id", app_id);
 	return uri;
@@ -195,11 +195,11 @@ QobuzClient::MakeSignedUrl(const char *object, const char *method,
 	QueryStringBuilder q;
 	std::string concatenated_query(object);
 	concatenated_query += method;
-	for (const auto &i : query) {
-		q(uri, i.first.c_str(), i.second.c_str());
+	for (const auto &[key, url] : query) {
+		q(uri, key.c_str(), url.c_str());
 
-		concatenated_query += i.first;
-		concatenated_query += i.second;
+		concatenated_query += key;
+		concatenated_query += url;
 	}
 
 	q(uri, "app_id", app_id);
diff --git a/src/lib/curl/Form.cxx b/src/lib/curl/Form.cxx
index 65430641d..5b668ec46 100644
--- a/src/lib/curl/Form.cxx
+++ b/src/lib/curl/Form.cxx
@@ -36,16 +36,16 @@ EncodeForm(CURL *curl,
 {
 	std::string result;
 
-	for (const auto &i : fields) {
+	for (const auto &[key, field] : fields) {
 		if (!result.empty())
 			result.push_back('&');
 
-		result.append(i.first);
+		result.append(key);
 		result.push_back('=');
 
-		if (!i.second.empty()) {
-			CurlString value(curl_easy_escape(curl, i.second.data(),
-							  i.second.length()));
+		if (!field.empty()) {
+			CurlString value(
+				curl_easy_escape(curl, field.data(), field.length()));
 			if (value)
 				result.append(value);
 		}
diff --git a/src/neighbor/plugins/UdisksNeighborPlugin.cxx b/src/neighbor/plugins/UdisksNeighborPlugin.cxx
index 687fff0e2..6d683a731 100644
--- a/src/neighbor/plugins/UdisksNeighborPlugin.cxx
+++ b/src/neighbor/plugins/UdisksNeighborPlugin.cxx
@@ -182,8 +182,8 @@ UdisksNeighborExplorer::GetList() const noexcept
 
 	NeighborExplorer::List result;
 
-	for (const auto &i : by_uri)
-		result.emplace_front(i.second);
+	for (const auto &[t, r] : by_uri)
+		result.emplace_front(r);
 	return result;
 }
 
diff --git a/src/output/Print.cxx b/src/output/Print.cxx
index 9f0b0ddc9..d05198710 100644
--- a/src/output/Print.cxx
+++ b/src/output/Print.cxx
@@ -40,8 +40,7 @@ printAudioDevices(Response &r, const MultipleOutputs &outputs)
 			 ao.GetName(), ao.GetPluginName(),
 			 ao.IsEnabled());
 
-		for (const auto &a : ao.GetAttributes())
-			r.Format("attribute: %s=%s\n",
-				 a.first.c_str(), a.second.c_str());
+		for (const auto &[attribute, value] : ao.GetAttributes())
+			r.Format("attribute: %s=%s\n", attribute.c_str(), value.c_str());
 	}
 }
diff --git a/src/output/plugins/WasapiOutputPlugin.cxx b/src/output/plugins/WasapiOutputPlugin.cxx
index 94fa1e647..97ddccd30 100644
--- a/src/output/plugins/WasapiOutputPlugin.cxx
+++ b/src/output/plugins/WasapiOutputPlugin.cxx
@@ -321,9 +321,11 @@ void WasapiOutput::Enable() {
 	device.reset();
 
 	if (enumerate_devices && SafeTry([this]() { EnumerateDevices(); })) {
-		for (const auto &desc : device_desc) {
-			FormatNotice(wasapi_output_domain, "Device \"%u\" \"%s\"",
-				     desc.first, desc.second.c_str());
+		for (const auto &[device, desc] : device_desc) {
+			FormatNotice(wasapi_output_domain,
+				     "Device \"%u\" \"%s\"",
+				     device,
+				     desc.c_str());
 		}
 	}
 
diff --git a/src/sticker/Print.cxx b/src/sticker/Print.cxx
index 3c3a9602b..5a558864c 100644
--- a/src/sticker/Print.cxx
+++ b/src/sticker/Print.cxx
@@ -31,6 +31,6 @@ sticker_print_value(Response &r,
 void
 sticker_print(Response &r, const Sticker &sticker)
 {
-	for (const auto &i : sticker.table)
-		sticker_print_value(r, i.first.c_str(), i.second.c_str());
+	for (const auto &[name, val] : sticker.table)
+		sticker_print_value(r, name.c_str(), val.c_str());
 }
diff --git a/src/tag/GenParseName.cxx b/src/tag/GenParseName.cxx
index 70bbf7c39..4582162b2 100644
--- a/src/tag/GenParseName.cxx
+++ b/src/tag/GenParseName.cxx
@@ -60,10 +60,7 @@ main(int argc, char **argv)
 
 	char first = 0;
 
-	for (const auto &i : names) {
-		const std::string_view name = i.first;
-		const TagType tag = i.second;
-
+	for (const auto &[name, tag] : names) {
 		if (name.front() != first) {
 			if (first != 0)
 				fprintf(out, "    break;\n\n");