src/types/quantity.rs

@@ -46,7 +46,7 @@ impl FromStr for QuantityUnit {
             MILLI_LITER => Ok(Self::MilliLiter),
             LITER => Ok(Self::Liter),
             MILLI_GRAM => Ok(Self::Milligram),
-            _ => Err("Currency unsupported".into()),
+            _ => Err(format!("Quantity unsupported: {s}")),
         }
     }
 }
@@ -74,6 +74,15 @@ impl QuantityPart {
             }
         }
     }
+
+    pub fn is_dividable(&self) -> bool {
+        match self.unit {
+            QuantityUnit::Kilogram | QuantityUnit::Liter | QuantityUnit::Gram => true,
+            QuantityUnit::Milligram | QuantityUnit::MilliLiter | QuantityUnit::DiscreteNumber => {
+                false
+            }
+        }
+    }
 }
 
 #[derive(