--- /dev/null
+/*=============================================================================
+ Copyright (c) 2001-2003 Hartmut Kaiser
+ http://spirit.sourceforge.net/
+
+ Use, modification and distribution is subject to the Boost Software
+ License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+ http://www.boost.org/LICENSE_1_0.txt)
+=============================================================================*/
+///////////////////////////////////////////////////////////////////////////////
+//
+// This example shows:
+// 1. Parsing of different comment styles
+// parsing C/C++-style comment
+// parsing C++-style comment
+// parsing PASCAL-style comment
+// 2. Parsing tagged data with the help of the confix_parser
+// 3. Parsing tagged data with the help of the confix_parser but the semantic
+// action is directly attached to the body sequence parser
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include <string>
+#include <iostream>
+#include <cassert>
+
+#include <boost/spirit/include/classic_core.hpp>
+#include <boost/spirit/include/classic_confix.hpp>
+#include <boost/spirit/include/classic_chset.hpp>
+
+
+///////////////////////////////////////////////////////////////////////////////
+// used namespaces
+using namespace std;
+using namespace BOOST_SPIRIT_CLASSIC_NS;
+
+///////////////////////////////////////////////////////////////////////////////
+// actor called after successfully matching a single character
+class actor_string
+{
+public:
+ actor_string(std::string &rstr) :
+ matched(rstr)
+ {
+ }
+
+ void operator() (const char *pbegin, const char *pend) const
+ {
+ matched += std::string(pbegin, pend-pbegin);
+ }
+
+private:
+ std::string &matched;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// actor called after successfully matching a C++-comment
+void actor_cpp (const char *pfirst, const char *plast)
+{
+ cout << "Parsing C++-comment" <<endl;
+ cout << "Matched (" << plast-pfirst << ") characters: ";
+ cout << "\"" << std::string(pfirst, plast) << "\"" << endl;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// main entry point
+int main ()
+{
+
+///////////////////////////////////////////////////////////////////////////////
+//
+// 1. Parsing different comment styles
+// parsing C/C++-style comments (non-nested!)
+//
+///////////////////////////////////////////////////////////////////////////////
+
+ char const* pCComment = "/* This is a /* nested */ C-comment */";
+
+ rule<> cpp_comment;
+
+ cpp_comment =
+ comment_p("/*", "*/") // rule for C-comments
+ | comment_p("//") // rule for C++ comments
+ ;
+
+ std::string comment_c;
+ parse_info<> result;
+
+ result = parse (pCComment, cpp_comment[actor_string(comment_c)]);
+ if (result.hit)
+ {
+ cout << "Parsed C-comment successfully!" << endl;
+ cout << "Matched (" << (int)comment_c.size() << ") characters: ";
+ cout << "\"" << comment_c << "\"" << endl;
+ }
+ else
+ {
+ cout << "Failed to parse C/C++-comment!" << endl;
+ }
+ cout << endl;
+
+ // parsing C++-style comment
+ char const* pCPPComment = "// This is a C++-comment\n";
+ std::string comment_cpp;
+
+ result = parse (pCPPComment, cpp_comment[&actor_cpp]);
+ if (result.hit)
+ cout << "Parsed C++-comment successfully!" << endl;
+ else
+ cout << "Failed to parse C++-comment!" << endl;
+
+ cout << endl;
+
+
+ // parsing PASCAL-style comment (nested!)
+ char const* pPComment = "{ This is a (* nested *) PASCAL-comment }";
+
+ rule<> pascal_comment;
+
+ pascal_comment = // in PASCAL we have two comment styles
+ comment_nest_p('{', '}') // both may be nested
+ | comment_nest_p("(*", "*)")
+ ;
+
+ std::string comment_pascal;
+
+ result = parse (pPComment, pascal_comment[actor_string(comment_pascal)]);
+ if (result.hit)
+ {
+ cout << "Parsed PASCAL-comment successfully!" << endl;
+ cout << "Matched (" << (int)comment_pascal.size() << ") characters: ";
+ cout << "\"" << comment_pascal << "\"" << endl;
+ }
+ else
+ {
+ cout << "Failed to parse PASCAL-comment!" << endl;
+ }
+ cout << endl;
+
+///////////////////////////////////////////////////////////////////////////////
+//
+// 2. Parsing tagged data with the help of the confix parser
+//
+///////////////////////////////////////////////////////////////////////////////
+
+ std::string body;
+ rule<> open_tag, html_tag, close_tag, body_text;
+
+ open_tag =
+ str_p("<b>")
+ ;
+
+ body_text =
+ anychar_p
+ ;
+
+ close_tag =
+ str_p("</b>")
+ ;
+
+ html_tag =
+ confix_p (open_tag, (*body_text)[actor_string(body)], close_tag)
+ ;
+
+ char const* pTag = "<b>Body text</b>";
+
+ result = parse (pTag, html_tag);
+ if (result.hit)
+ {
+ cout << "Parsed HTML snippet \"<b>Body text</b>\" successfully "
+ "(with re-attached actor)!" << endl;
+ cout << "Found body (" << (int)body.size() << " characters): ";
+ cout << "\"" << body << "\"" << endl;
+ }
+ else
+ {
+ cout << "Failed to parse HTML snippet (with re-attached actor)!"
+ << endl;
+ }
+ cout << endl;
+
+///////////////////////////////////////////////////////////////////////////////
+//
+// 3. Parsing tagged data with the help of the confix_parser but the
+// semantic action is directly attached to the body sequence parser
+// (see comment in confix.hpp) and out of the usage of the 'direct()'
+// construction function no automatic refactoring takes place.
+//
+// As you can see, for successful parsing it is required to refactor the
+// confix parser by hand. To see, how it fails, you can try the following:
+//
+// html_tag_direct =
+// confix_p.direct(
+// str_p("<b>"),
+// (*body_text)[actor_string(bodydirect)],
+// str_p("</b>")
+// )
+// ;
+//
+// Here the *body_text parser eats up all the input up to the end of the
+// input sequence.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+ rule<> html_tag_direct;
+ std::string bodydirect;
+
+ html_tag_direct =
+ confix_p.direct(
+ str_p("<b>"),
+ (*(body_text - str_p("</b>")))[actor_string(bodydirect)],
+ str_p("</b>")
+ )
+ ;
+
+ char const* pTagDirect = "<b>Body text</b>";
+
+ result = parse (pTagDirect, html_tag_direct);
+ if (result.hit)
+ {
+ cout << "Parsed HTML snippet \"<b>Body text</b>\" successfully "
+ "(with direct actor)!" << endl;
+ cout << "Found body (" << (int)bodydirect.size() << " characters): ";
+ cout << "\"" << bodydirect << "\"" << endl;
+ }
+ else
+ {
+ cout << "Failed to parse HTML snippet (with direct actor)!" << endl;
+ }
+ cout << endl;
+
+ return 0;
+}
projects / ceph.git / blobdiff