congr_error_msg.lean:9:0: error: invalid [congr] lemma, 'C₁' the left-hand-side of the congruence resulting type must be of the form (g x_1 ... x_n), where each x_i is a distinct variable or a sort
congr_error_msg.lean:12:0: error: invalid [congr] lemma, 'C₂' resulting type is not of the form (g  ...) ~ (g ...), where ~ is 'eq'
congr_error_msg.lean:15:0: error: invalid [congr] lemma, 'C₃' resulting type is not of the form t ~ s, where '~' is a transitive and reflexive relation
congr_error_msg.lean:21:0: error: invalid [congr] lemma, 'C₅' left-hand-side of the congruence resulting type must be of the form (fun/Pi (x : A), B x)
congr_error_msg.lean:24:0: error: invalid [congr] lemma, 'C₆' left-hand-side is not an application nor a binding
congr_error_msg.lean:27:0: error: invalid [congr] lemma, 'C₇' argument #2 of parameter #5 contains unresolved parameters
congr_error_msg.lean:30:0: error: invalid [congr] lemma, 'C₈' argument #5 is not a valid hypothesis, the left-hand-side contains unresolved parameters
congr_error_msg.lean:33:0: error: invalid [congr] lemma, 'C₉' argument #6 is not a valid hypothesis, the right-hand-side must be of the form (m l_1 ... l_n) where m is parameter that was not 'assigned/resolved' yet and l_i's are locals
congr_error_msg.lean:33:0: error: unknown declaration 'C₁'