n>
  <a href="#type-abduction_result">abduction_result</a></span></code></div><div class="spec-doc"><p>given <code>arith_lhs_opt bop arith_rhs_opt</code> and if not <code>negated</code>, return either</p><ul><li><code>Unsatisfiable</code> iff lhs bop rhs = ∅</li></ul><ul><li><code>Satisfiable (abduced_lhs_opt,abduced_rhs_opt)</code> iff lhs bop rhs ≠ ∅, such that (taking lhs=true if lhs_opt is <code>None</code>, same for rhs) <code>abduced_lhs_opt=Some alhs</code> if (lhs bop rhs ≠ ∅ =&gt; alhs⇔