le_eq_trans a d e (le_trans a c d (eq_le_trans a b c H1 H2) H3) H4 : a ≤ e
calc1.lean:38:10: error: invalid 'calc' expression, transitivity rule is not defined for current step
le_lt_trans b c d H2 H5 : b < d
[choice (@le2_trans b d e (@le2_trans b c d H2 H3) H4) (@le_trans b d e (@le_trans b c d H2 H3) H4)]