a b Fatal error: exception Backtrace.Error("b") Raised at Backtrace.f in file "backtrace.ml", line 11, characters 16-32 Called from Backtrace.f in file "backtrace.ml", line 11, characters 42-53 Called from Backtrace.f in file "backtrace.ml", line 11, characters 42-53 Called from Backtrace.f in file "backtrace.ml", line 11, characters 42-53 Called from Backtrace.f in file "backtrace.ml", line 11, characters 42-53 Called from Backtrace.f in file "backtrace.ml", line 11, characters 42-53 Called from Backtrace.g in file "backtrace.ml", line 15, characters 4-11 Re-raised at Backtrace.g in file "backtrace.ml", line 17, characters 62-71 Called from Backtrace in file "backtrace.ml", line 21, characters 9-25 Fatal error: exception Backtrace.Error("c") Raised at Backtrace.g in file "backtrace.ml", line 18, characters 20-37 Called from Backtrace in file "backtrace.ml", line 21, characters 9-25 Fatal error: exception Backtrace.Error("d") Raised at Backtrace.f in file "backtrace.ml", line 11, characters 16-32 Called from Backtrace.f in file "backtrace.ml", line 11, characters 42-53 Called from Backtrace.f in file "backtrace.ml", line 11, characters 42-53 Called from Backtrace.f in file "backtrace.ml", line 11, characters 42-53 Called from Backtrace.f in file "backtrace.ml", line 11, characters 42-53 Called from Backtrace.f in file "backtrace.ml", line 11, characters 42-53 Called from Backtrace.g in file "backtrace.ml", line 15, characters 4-11 Called from Backtrace in file "backtrace.ml", line 21, characters 9-25 Fatal error: exception Invalid_argument("index out of bounds") Raised by primitive operation at Backtrace in file "backtrace.ml", line 21, characters 12-24