Userland: static vs non-static constexpr variables

Problem:
- `static` variables consume memory and sometimes are less
  optimizable.
- `static const` variables can be `constexpr`, usually.
- `static` function-local variables require an initialization check
  every time the function is run.

Solution:
- If a global `static` variable is only used in a single function then
  move it into the function and make it non-`static` and `constexpr`.
- Make all global `static` variables `constexpr` instead of `const`.
- Change function-local `static const[expr]` variables to be just
  `constexpr`.

Userland/Applications/Browser/CookieJar.cpp

@@ -7,6 +7,7 @@
 #include "CookieJar.h"
 #include <AK/IPv4Address.h>
 #include <AK/StringBuilder.h>
+#include <AK/StringView.h>
 #include <AK/URL.h>
 #include <AK/Vector.h>
 #include <LibWeb/Cookie/ParsedCookie.h>
@@ -48,9 +49,9 @@ void CookieJar::set_cookie(const URL& url, const Web::Cookie::ParsedCookie& pars
 
 void CookieJar::dump_cookies() const
 {
-    static const char* key_color = "\033[34;1m";
-    static const char* attribute_color = "\033[33m";
-    static const char* no_color = "\033[0m";
+    constexpr StringView key_color = "\033[34;1m";
+    constexpr StringView attribute_color = "\033[33m";
+    constexpr StringView no_color = "\033[0m";
 
     StringBuilder builder;
     builder.appendff("{} cookies stored\n", m_cookies.size());

Userland/Applications/Calendar/AddEventDialog.cpp

@@ -5,6 +5,7 @@
  */
 
 #include "AddEventDialog.h"
+#include <AK/StringView.h>
 #include <LibCore/DateTime.h>
 #include <LibGUI/BoxLayout.h>
 #include <LibGUI/Button.h>
@@ -20,11 +21,6 @@
 #include <LibGfx/Font.h>
 #include <LibGfx/FontDatabase.h>
 
-static const char* short_month_names[] = {
-    "Jan", "Feb", "Mar", "Apr", "May", "Jun",
-    "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
-};
-
 AddEventDialog::AddEventDialog(Core::DateTime date_time, Window* parent_window)
     : Dialog(parent_window)
     , m_date_time(date_time)
@@ -121,6 +117,11 @@ String AddEventDialog::MonthListModel::column_name(int column) const
 
 GUI::Variant AddEventDialog::MonthListModel::data(const GUI::ModelIndex& index, GUI::ModelRole role) const
 {
+    constexpr StringView short_month_names[] = {
+        "Jan", "Feb", "Mar", "Apr", "May", "Jun",
+        "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
+    };
+
     auto& month = short_month_names[index.row()];
     if (role == GUI::ModelRole::Display) {
         switch (index.column()) {

Userland/Applications/FontEditor/FontEditor.cpp

@@ -9,6 +9,7 @@
 #include "GlyphMapWidget.h"
 #include "NewFontDialog.h"
 #include <AK/StringBuilder.h>
+#include <AK/StringView.h>
 #include <AK/UnicodeUtils.h>
 #include <Applications/FontEditor/FontEditorWindowGML.h>
 #include <LibDesktop/Launcher.h>
@@ -37,19 +38,19 @@
 #include <LibGfx/TextDirection.h>
 #include <stdlib.h>
 
-static constexpr int s_pangram_count = 7;
-static const char* pangrams[s_pangram_count] = {
-    "quick fox jumps nightly above wizard",
-    "five quacking zephyrs jolt my wax bed",
-    "pack my box with five dozen liquor jugs",
-    "quick brown fox jumps over the lazy dog",
-    "waxy and quivering jocks fumble the pizza",
-    "~#:[@_1%]*{$2.3}/4^(5'6\")-&|7+8!=<9,0\\>?;",
-    "byxfjärmat föl gick på duvshowen"
-};
-
 static RefPtr<GUI::Window> create_font_preview_window(FontEditorWidget& editor)
 {
+    constexpr int pangram_count = 7;
+    constexpr StringView pangrams[pangram_count] = {
+        "quick fox jumps nightly above wizard",
+        "five quacking zephyrs jolt my wax bed",
+        "pack my box with five dozen liquor jugs",
+        "quick brown fox jumps over the lazy dog",
+        "waxy and quivering jocks fumble the pizza",
+        "~#:[@_1%]*{$2.3}/4^(5'6\")-&|7+8!=<9,0\\>?;",
+        "byxfjärmat föl gick på duvshowen"
+    };
+
     auto window = GUI::Window::construct();
     window->set_window_type(GUI::WindowType::ToolWindow);
     window->set_title("Font preview");
@@ -94,7 +95,7 @@ static RefPtr<GUI::Window> create_font_preview_window(FontEditorWidget& editor)
     reload_button.set_fixed_width(22);
     reload_button.on_click = [&] {
         static int i = 1;
-        if (i >= s_pangram_count)
+        if (i >= pangram_count)
             i = 0;
         preview_textbox.set_text(pangrams[i]);
         i++;

Userland/Applications/HexEditor/FindDialog.cpp

@@ -5,9 +5,9 @@
  */
 
 #include "FindDialog.h"
+#include <AK/Array.h>
 #include <AK/Hex.h>
 #include <AK/String.h>
-#include <AK/Vector.h>
 #include <LibGUI/BoxLayout.h>
 #include <LibGUI/Button.h>
 #include <LibGUI/Label.h>
@@ -19,17 +19,12 @@
 #include <LibGfx/FontDatabase.h>
 
 struct Option {
-    String title;
+    StringView title;
     OptionId opt;
     bool enabled;
     bool default_action;
 };
 
-static const Vector<Option> options = {
-    { "ACII String", OPTION_ASCII_STRING, true, true },
-    { "Hex value", OPTION_HEX_VALUE, true, false },
-};
-
 int FindDialog::show(GUI::Window* parent_window, String& out_text, ByteBuffer& out_buffer)
 {
     auto dialog = FindDialog::construct();
@@ -88,6 +83,11 @@ Result<ByteBuffer, String> FindDialog::process_input(String text_value, OptionId
 FindDialog::FindDialog()
     : Dialog(nullptr)
 {
+    constexpr Array options = {
+        Option { "ACII String", OPTION_ASCII_STRING, true, true },
+        Option { "Hex value", OPTION_HEX_VALUE, true, false },
+    };
+
     resize(280, 180 + ((static_cast<int>(options.size()) - 3) * 16));
     center_on_screen();
     set_resizable(false);
@@ -113,7 +113,7 @@ FindDialog::FindDialog()
         radio.set_enabled(action.enabled);
         radio.set_text(action.title);
 
-        radio.on_checked = [this, i](auto) {
+        radio.on_checked = [&](auto) {
             m_selected_option = options[i].opt;
         };
 

Userland/Applications/SpaceAnalyzer/TreeMapWidget.cpp

@@ -5,6 +5,7 @@
  */
 
 #include "TreeMapWidget.h"
+#include <AK/Array.h>
 #include <AK/NumberFormat.h>
 #include <LibGUI/Painter.h>
 #include <LibGUI/WindowServerConnection.h>
@@ -24,7 +25,7 @@ TreeMapWidget::~TreeMapWidget()
 {
 }
 
-static const Color colors[] = {
+static constexpr Array colors = {
     Color(253, 231, 37),
     Color(148, 216, 64),
     Color(60, 188, 117),

Userland/Applications/SpaceAnalyzer/main.cpp

@@ -9,6 +9,7 @@
 #include <AK/Queue.h>
 #include <AK/QuickSort.h>
 #include <AK/RefCounted.h>
+#include <AK/StringView.h>
 #include <AK/URL.h>
 #include <Applications/SpaceAnalyzer/SpaceAnalyzerGML.h>
 #include <LibCore/DirIterator.h>
@@ -27,8 +28,6 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
-static const char* APP_NAME = "Space Analyzer";
-
 struct TreeNode : public SpaceAnalyzer::TreeMapNode {
     TreeNode(String name)
         : m_name(move(name)) {};
@@ -253,6 +252,8 @@ static String get_absolute_path_to_selected_node(const SpaceAnalyzer::TreeMapWid
 
 int main(int argc, char* argv[])
 {
+    constexpr StringView APP_NAME = "Space Analyzer";
+
     auto app = GUI::Application::construct(argc, argv);
 
     RefPtr<Tree> tree = adopt_ref(*new Tree(""));