Binary package “styx” in ubuntu eoan

combined parser/scanner generator for C/C++

 The package facilitates application development including
 user-defined context free languages.
 .
 Its development model deviates from the traditional lex/yacc pair
 (flex/bison in Debian) by automating tedious tasks which are
 commonly implemented in yacc's actions.
 .
 Styx automatically derives a depth grammar, generates reentrant
 parsers that support persistent derivation trees, preserve full
 source information, support Unicode and are thread safe.