Start adding Perl verb support with FAIL as the first supported verb.

include/boost/regex/v4/basic_regex_parser.hpp

@@ -68,6 +68,8 @@ public:
    bool parse_inner_set(basic_char_set<charT, traits>& char_set);
    bool parse_QE();
    bool parse_perl_extension();
+   bool parse_perl_verb();
+   bool match_verb(const char*);
    bool add_emacs_code(bool negate);
    bool unwind_alts(std::ptrdiff_t last_paren_start);
    digraph<charT> get_next_set_literal(basic_char_set<charT, traits>& char_set);
@@ -421,6 +423,8 @@ bool basic_regex_parser<charT, traits>::parse_open_paren()
    {
       if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_question)
          return parse_perl_extension();
+      if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_star)
+         return parse_perl_verb();
    }
    //
    // update our mark count, and append the required state:
@@ -2652,6 +2656,70 @@ option_group_jump:
    return true;
 }
 
+template <class charT, class traits>
+bool basic_regex_parser<charT, traits>::match_verb(const char* verb)
+{
+   while(*verb)
+   {
+      if(static_cast<charT>(*verb) != *m_position)
+      {
+         while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position;
+         fail(regex_constants::error_perl_extension, m_position - m_base);
+         return false;
+      }
+      if(++m_position == m_end)
+      {
+         --m_position;
+         while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position;
+         fail(regex_constants::error_perl_extension, m_position - m_base);
+         return false;
+      }
+      ++verb;
+   }
+   return true;
+}
+
+template <class charT, class traits>
+bool basic_regex_parser<charT, traits>::parse_perl_verb()
+{
+   if(++m_position == m_end)
+   {
+      // Rewind to start of (* sequence:
+      --m_position;
+      while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position;
+      fail(regex_constants::error_perl_extension, m_position - m_base);
+      return false;
+   }
+   switch(*m_position)
+   {
+   case 'F':
+      if(++m_position == m_end)
+      {
+         // Rewind to start of (* sequence:
+         --m_position;
+         while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position;
+         fail(regex_constants::error_perl_extension, m_position - m_base);
+         return false;
+      }
+      if((this->m_traits.syntax_type(*m_position) == regex_constants::syntax_close_mark) || match_verb("AIL"))
+      {
+         if((m_position == m_end) || (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark))
+         {
+            // Rewind to start of (* sequence:
+            --m_position;
+            while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position;
+            fail(regex_constants::error_perl_extension, m_position - m_base);
+            return false;
+         }
+         ++m_position;
+         this->append_state(syntax_element_fail);
+         return true;
+      }
+      return false;
+   }
+   return false;
+}
+
 template <class charT, class traits>
 bool basic_regex_parser<charT, traits>::add_emacs_code(bool negate)
 {

include/boost/regex/v4/perl_matcher.hpp

@@ -443,6 +443,7 @@ private:
    bool backtrack_till_match(std::size_t count);
 #endif
    bool match_recursion();
+   bool match_fail();
 
    // find procs stored in s_find_vtable:
    bool find_restart_any();

include/boost/regex/v4/perl_matcher_common.hpp

@@ -793,6 +793,13 @@ bool perl_matcher<BidiIterator, Allocator, traits>::match_toggle_case()
    return true;
 }
 
+template <class BidiIterator, class Allocator, class traits>
+bool perl_matcher<BidiIterator, Allocator, traits>::match_fail()
+{
+   // Just force a backtrack:
+   return false;
+}
+
 
 template <class BidiIterator, class Allocator, class traits>
 bool perl_matcher<BidiIterator, Allocator, traits>::find_restart_any()

include/boost/regex/v4/perl_matcher_non_recursive.hpp

@@ -141,7 +141,7 @@ struct saved_recursion : public saved_state
 template <class BidiIterator, class Allocator, class traits>
 bool perl_matcher<BidiIterator, Allocator, traits>::match_all_states()
 {
-   static matcher_proc_type const s_match_vtable[30] = 
+   static matcher_proc_type const s_match_vtable[31] = 
    {
       (&perl_matcher<BidiIterator, Allocator, traits>::match_startmark),
       &perl_matcher<BidiIterator, Allocator, traits>::match_endmark,
@@ -177,6 +177,7 @@ bool perl_matcher<BidiIterator, Allocator, traits>::match_all_states()
       &perl_matcher<BidiIterator, Allocator, traits>::match_assert_backref,
       &perl_matcher<BidiIterator, Allocator, traits>::match_toggle_case,
       &perl_matcher<BidiIterator, Allocator, traits>::match_recursion,
+      &perl_matcher<BidiIterator, Allocator, traits>::match_fail,
    };
 
    push_recursion_stopper();

include/boost/regex/v4/perl_matcher_recursive.hpp

@@ -60,7 +60,7 @@ public:
 template <class BidiIterator, class Allocator, class traits>
 bool perl_matcher<BidiIterator, Allocator, traits>::match_all_states()
 {
-   static matcher_proc_type const s_match_vtable[30] = 
+   static matcher_proc_type const s_match_vtable[31] = 
    {
       (&perl_matcher<BidiIterator, Allocator, traits>::match_startmark),
       &perl_matcher<BidiIterator, Allocator, traits>::match_endmark,
@@ -96,6 +96,7 @@ bool perl_matcher<BidiIterator, Allocator, traits>::match_all_states()
       &perl_matcher<BidiIterator, Allocator, traits>::match_assert_backref,
       &perl_matcher<BidiIterator, Allocator, traits>::match_toggle_case,
       &perl_matcher<BidiIterator, Allocator, traits>::match_recursion,
+      &perl_matcher<BidiIterator, Allocator, traits>::match_fail,
    };
 
    if(state_count > max_state_count)

include/boost/regex/v4/states.hpp

@@ -120,7 +120,9 @@ enum syntax_element_type
    syntax_element_assert_backref = syntax_element_backstep + 1,
    syntax_element_toggle_case = syntax_element_assert_backref + 1,
    // a recursive expression:
-   syntax_element_recurse = syntax_element_toggle_case + 1
+   syntax_element_recurse = syntax_element_toggle_case + 1,
+   // Verbs:
+   syntax_element_fail = syntax_element_recurse + 1,
 };
 
 #ifdef BOOST_REGEX_DEBUG

test/regress/main.cpp

@@ -82,6 +82,7 @@ void run_tests()
    RUN_TESTS(test_pocessive_repeats);
    RUN_TESTS(test_mark_resets);
    RUN_TESTS(test_recursion);
+   RUN_TESTS(test_verbs);
 }
 
 int cpp_main(int /*argc*/, char * /*argv*/[])

test/regress/test.hpp

@@ -288,5 +288,6 @@ void test_unicode();
 void test_pocessive_repeats();
 void test_mark_resets();
 void test_recursion();
+void test_verbs();
 
 #endif

test/regress/test_perl_ex.cpp

@@ -932,3 +932,11 @@ void test_recursion()
    TEST_REGEX_SEARCH("(?:(?<A>a+)|(?<A>b+)|c+)\\.\\k<A>", perl, "cccc.cccc", match_default, make_array(-2, -2));
 }
 
+void test_verbs()
+{
+   using namespace boost::regex_constants;
+
+   TEST_INVALID_REGEX("a+(*", perl);
+   TEST_INVALID_REGEX("a+(*FX)", perl);
+   TEST_REGEX_SEARCH("a+(*FAIL)b", perl, "aaaab", match_default, make_array(-2, -2));
+}