Extract common main function of examples

example/example_parser.hpp

@@ -0,0 +1,51 @@
+// Copyright (C) 2017 Jonathan Müller <jonathanmueller.dev@gmail.com>
+// This file is subject to the license terms in the LICENSE file
+// found in the top-level directory of this distribution.
+
+#ifndef CPPAST_EXAMPLE_PARSER_HPP_INCLUDED
+#define CPPAST_EXAMPLE_PARSER_HPP_INCLUDED
+
+#include <iostream>
+
+#include <cppast/libclang_parser.hpp>
+
+// reads the database directory from the command line argument
+// parses all files in that directory
+// and invokes the callback for each of them
+template <typename Callback>
+int example_main(int argc, char* argv[], const cppast::cpp_entity_index& index, Callback cb)
+{
+    if (argc != 2)
+    {
+        std::cerr << "usage: " << argv[0] << " <compile-commands-json-dir>\n";
+        return 1;
+    }
+    else
+    {
+        cppast::libclang_compilation_database database(argv[1]); // the compilation database
+
+        // simple_file_parser allows parsing multiple files and stores the results for us
+        cppast::simple_file_parser<cppast::libclang_parser> parser(type_safe::ref(index));
+        try
+        {
+            cppast::parse_database(parser, database); // parse all files in the database
+        }
+        catch (cppast::libclang_error& ex)
+        {
+            std::cerr << "fatal libclang error: " << ex.what() << '\n';
+            return 1;
+        }
+
+        if (parser.error())
+            // a non-fatal parse error
+            // error has been logged to stderr
+            return 1;
+
+        for (auto& file : parser.files())
+            cb(file);
+    }
+
+    return 0;
+}
+
+#endif // CPPAST_EXAMPLE_PARSER_HPP_INCLUDED