<https://github.com/quasar-analytics/purescript-mra/blob/bbe143cfe1e96160c578c01142c638f5c88c57ea/src/MRA/Core.purs#L126>
https://github.com/quasar-analytics/purescript-mra/blob/bbe143cfe1e96160c578c01142c638f5c88c57ea/src/MRA/Core.purs#L126