Solved this problem years ago for Algol68 (which allows you to specify relative precedence) by parsing with an LALR generated parser that left the resulting shi

Solved this problem years ago for Algol68 (which allows you to specify relative precedence) by parsing with an LALR generated parser that left the resulting shift/reduce conflict to be resolved at run time (by looking at the operator on the stack and the one just scanned and comparing their current precedences)