LR(k) parser construction.
TODO: * conflict handling o statically o by priority o by associativity o dynamically o user-defined predicate o make attributes available o automatically o transparently change the grammar o can I use the same declarations for scanner and ll and lr? o scanner conflicts are usually solved implicitly, using sequencing information; this may become explicit o other tools o Eli o offers to change the lookahead o lex, yacc, syntax o priority for token; inherited to productions o priority for productions o associativity