| ## The `NonlinearArith` module {#sec-nonlinear-arith} | |
| Non-linear math uses operations like multiplication, division and modulo (where neither argument is a literal integer). Reasoning problems using non-linear arithmetic are generally undecidable; hence Dafny (and Z3) rely on heuristics to prove such properties. | |
| While wonderful when they work, these heuristics can lead to unstable proofs. Hence, in many projects, | |
| it can be helpful to turn off these heuristics (via Dafny's `--disable-nonlinear-arithmetic` flag) and instead explicitly | |
| invoke the lemmas in this library. All files in this portion of the library (except those in `Internals/*Nonlinear.dfy`) | |
| verify with the `--disable-nonlinear-arithmetic` flag, which should keep the library itself stable. | |
| In general, it shouldn't be necessary to directly reference anything in `Internals`. | |