Goal:
    x : t  y : t  Heq_anonymous : true = eqb x y
  ============================
   (x = y)


DEBUG:Going to execute:
try Tactics.discriminates
Level 1: Backtrace:

No matching clauses for match.
Level 1: evaluation
raised the exception
Backtrace:

No matching clauses for match.

Level 2: Backtrace:

No matching clauses for match.
Level 1: Backtrace:

No matching clauses for match.
Level 1: Backtrace:

No matching clauses for match.
Level 0: Backtrace:

No matching clauses for match.
Level 1: Backtrace:

No matching clauses for match.
Level 0: Backtrace:

No matching clauses for match.
Level 0: Backtrace:

No matching clauses for match.