'--skeleton': give more info when reporting unused data and keys.

diff --git a/re2c/src/codegen/skeleton/generate_code.cc b/re2c/src/codegen/skeleton/generate_code.cc
index 5484e0b32803847e4d8cb72c29d53ae08920be32..da3735d309e18f881e47886b2af39fa424ea9fcf 100644 (file)
--- a/re2c/src/codegen/skeleton/generate_code.cc
+++ b/re2c/src/codegen/skeleton/generate_code.cc
@@ -173,6 +173,7 @@ void Skeleton::emit_start
        o << "\n" << ind << "YYKEYTYPE * keys = NULL;";
        o << "\n" << ind << "const YYCTYPE * cursor = NULL;";
        o << "\n" << ind << "const YYCTYPE * limit = NULL;";
+       o << "\n" << ind << "const YYCTYPE * token = NULL;";
        o << "\n" << ind << "const YYCTYPE * eof = NULL;";
        o << "\n" << ind << "unsigned int i = 0;";
        o << "\n";
@@ -206,6 +207,7 @@ void Skeleton::emit_start
        o << "\n";
        o << "\n" << ind << "for (i = 0; status == 0 && i < keys_count; ++i)";
        o << "\n" << ind << "{";
+       o << "\n" << ind << ind << "token = cursor;";
        if (backup)
        {
                o << "\n" << ind << ind << "const YYCTYPE * marker = NULL;";
@@ -214,7 +216,6 @@ void Skeleton::emit_start
        {
                o << "\n" << ind << ind << "const YYCTYPE * ctxmarker = NULL;";
        }
-       o << "\n" << ind << ind << "const YYCTYPE * token = cursor;";
        o << "\n" << ind << ind << "YYCTYPE yych;";
        if (accept)
        {
@@ -242,12 +243,13 @@ void Skeleton::emit_end
        o << "\n" << ind << ind << "if (cursor != eof)";
        o << "\n" << ind << ind << "{";
        o << "\n" << ind << ind << ind << "status = 1;";
-       o << "\n" << ind << ind << ind << "fprintf (stderr, \"error: lex_" << name << ": unused input strings left\\n\");";
+       o << "\n" << ind << ind << ind << "const long pos = token - input;";
+       o << "\n" << ind << ind << ind << "fprintf (stderr, \"error: lex_" << name << ": unused input strings left at position %ld\\n\", pos);";
        o << "\n" << ind << ind << "}";
        o << "\n" << ind << ind << "if (i != keys_count)";
        o << "\n" << ind << ind << "{";
        o << "\n" << ind << ind << ind << "status = 1;";
-       o << "\n" << ind << ind << ind << "fprintf (stderr, \"error: lex_" << name << ": unused keys left\\n\");";
+       o << "\n" << ind << ind << ind << "fprintf (stderr, \"error: lex_" << name << ": unused keys left after %u iterations\\n\", i);";
        o << "\n" << ind << ind << "}";
        o << "\n" << ind << "}";
        o << "\n";