Fix formatting and simplify

Since @irevoire fixed problems arrising from calls to simplify, a lot of rounding/conversion bugs have been solved by extension. This lets the function work with a far simpler implementation.

numbat/modules/core/mixed_units.nbt

@@ -29,15 +29,13 @@ fn _mixed_units<D: Dim>(q: D, units: List<D>, names: List<String>, round_last: B
 
 fn _zero_length<A: Dim>(val: A) -> A = val * 0 -> val
 
-
-fn _mixed_unit_list<A: Dim>(val: A, units: List<A>, min_unit: A, acc: List<A>) -> List<A> =
-  if trunc_in(min_unit, val) == 0
-  then concat(acc, map(_zero_length, units))
-  else if len(units) == 1
-  then cons_end(val -> head(units), acc)
-  else _mixed_unit_list(val - unit_val, tail(units), min_unit, cons_end(unit_val, acc))
-  where unit_val: A =
+fn _mixed_unit_list<D: Dim>(val: D, units: List<D>, acc: List<D>) -> List<D> =
+  if val == 0
+    then concat(acc, map(_zero_length, units))
+    else if len(units) == 1
+      then cons_end(val -> head(units), acc)
+      else _mixed_unit_list(val - unit_val, tail(units), cons_end(unit_val, acc))
+  where unit_val: D =
     if (len(units) > 0)
-    then (val |> round_in(min_unit) |> trunc_in(head(units)))
-    else error("Units list cannot be empty")
-
+      then (val |> trunc_in(head(units)))
+      else error("Units list cannot be empty")

numbat/modules/units/mixed.nbt

@@ -28,5 +28,5 @@ fn pounds_and_ounces(mass: Mass) -> String =
 
 
 @name("Unit list")
-@description("Convert a value to a mixed representation using the provided units.)
-fn unit_list<A: Dim>(units: List<A>, value: A) -> List<A> = _mixed_unit_list(value, units, minimum(units) / 100, [])
+@description("Convert a value to a mixed representation using the provided units.")
+fn unit_list<D: Dim>(units: List<D>, value: D) -> List<D> = _mixed_unit_list(value, units, [])