boost::regex optimization (building regexes can be somewhat resource demanding)

src/cmake.cc

@@ -8,7 +8,7 @@
 CMake::CMake(const boost::filesystem::path &path) {
   const auto find_cmake_project=[this](const boost::filesystem::path &cmake_path) {
     for(auto &line: filesystem::read_lines(cmake_path)) {
-      const boost::regex project_regex("^ *project *\\(.*$", boost::regex::icase);
+      const static boost::regex project_regex("^ *project *\\(.*$", boost::regex::icase);
       boost::smatch sm;
       if(boost::regex_match(line, sm, project_regex))
         return true;
@@ -207,7 +207,7 @@ void CMake::find_variables() {
       if(end_line>start_line) {
         auto line=file.substr(start_line, end_line-start_line);
         boost::smatch sm;
-        const boost::regex set_regex("^ *set *\\( *([A-Za-z_][A-Za-z_0-9]*) +(.*)\\) *$", boost::regex::icase);
+        const static boost::regex set_regex("^ *set *\\( *([A-Za-z_][A-Za-z_0-9]*) +(.*)\\) *$", boost::regex::icase);
         if(boost::regex_match(line, sm, set_regex)) {
           auto data=sm[2].str();
           while(data.size()>0 && data.back()==' ')
@@ -216,7 +216,7 @@ void CMake::find_variables() {
           variables[sm[1].str()]=data;
         }
         else {
-          const boost::regex project_regex("^ *project *\\( *([^ ]+).*\\) *$", boost::regex::icase);
+          const static boost::regex project_regex("^ *project *\\( *([^ ]+).*\\) *$", boost::regex::icase);
           if(boost::regex_match(line, sm, project_regex)) {
             auto data=sm[1].str();
             parse_variable_parameters(data);

src/source.cc

@@ -79,6 +79,10 @@ std::string Source::FixIt::string(Glib::RefPtr<Gtk::TextBuffer> buffer) {
 //////////////
 //// View ////
 //////////////
+const boost::regex Source::View::bracket_regex("^([ \\t]*).*\\{ *$");
+const boost::regex Source::View::no_bracket_statement_regex("^([ \\t]*)(if|for|else if|while) *\\(.*[^;}] *$");
+const boost::regex Source::View::no_bracket_no_para_statement_regex("^([ \\t]*)(else) *$");
+
 AspellConfig* Source::View::spellcheck_config=NULL;
 
 Source::View::View(const boost::filesystem::path &file_path, Glib::RefPtr<Gsv::Language> language): file_path(file_path), language(language) {
@@ -271,10 +275,6 @@ Source::View::View(const boost::filesystem::path &file_path, Glib::RefPtr<Gsv::L
   
   set_tooltip_and_dialog_events();
   
-  bracket_regex=boost::regex("^([ \\t]*).*\\{ *$");
-  no_bracket_statement_regex=boost::regex("^([ \\t]*)(if|for|else if|while) *\\(.*[^;}] *$");
-  no_bracket_no_para_statement_regex=boost::regex("^([ \\t]*)(else) *$");
-  
   if(language && (language->get_id()=="chdr" || language->get_id()=="cpphdr" || language->get_id()=="c" ||
                   language->get_id()=="cpp" || language->get_id()=="objc" || language->get_id()=="java" ||
                   language->get_id()=="js" || language->get_id()=="ts" || language->get_id()=="proto" ||

src/source.h

@@ -138,9 +138,9 @@ namespace Source {
     bool find_right_bracket_forward(Gtk::TextIter iter, Gtk::TextIter &found_iter);
     bool find_left_bracket_backward(Gtk::TextIter iter, Gtk::TextIter &found_iter);
     
-    boost::regex bracket_regex;
-    boost::regex no_bracket_statement_regex;
-    boost::regex no_bracket_no_para_statement_regex;
+    const static boost::regex bracket_regex;
+    const static boost::regex no_bracket_statement_regex;
+    const static boost::regex no_bracket_no_para_statement_regex;
     
     bool on_key_press_event(GdkEventKey* key) override;
     bool on_key_press_event_basic(GdkEventKey* key);

src/source_clang.cc

@@ -187,7 +187,7 @@ std::vector<std::string> Source::ClangViewParse::get_compilation_commands() {
     }
   }
   auto clang_version_string=clang::to_string(clang_getClangVersion());
-  const boost::regex clang_version_regex("^[A-Za-z ]+([0-9.]+).*$");
+  const static boost::regex clang_version_regex("^[A-Za-z ]+([0-9.]+).*$");
   boost::smatch sm;
   if(boost::regex_match(clang_version_string, sm, clang_version_regex)) {
     auto clang_version=sm[1].str();
@@ -634,8 +634,8 @@ void Source::ClangViewAutocomplete::autocomplete_check() {
                                                       get_source_buffer()->iter_has_context_class(iter, "comment")))
     return;
   std::string line=" "+get_line_before();
-  const boost::regex in_specified_namespace("^(.*[a-zA-Z0-9_\\)\\]\\>])(->|\\.|::)([a-zA-Z0-9_]*)$");
-  const boost::regex within_namespace("^(.*)([^a-zA-Z0-9_]+)([a-zA-Z0-9_]{3,})$");
+  const static boost::regex in_specified_namespace("^(.*[a-zA-Z0-9_\\)\\]\\>])(->|\\.|::)([a-zA-Z0-9_]*)$");
+  const static boost::regex within_namespace("^(.*)([^a-zA-Z0-9_]+)([a-zA-Z0-9_]{3,})$");
   boost::smatch sm;
   if(boost::regex_match(line, sm, in_specified_namespace)) {
     {