operator to use an ingredient

cout-recette.hs

@@ -24,6 +24,9 @@ unitCost (Recipe _ _ qtt _) totalCost = totalCost / qtt
 useCost :: Recipe -> Double -> Double
 useCost (Recipe _ _ _ uses) totalCost = totalCost / uses
 
+(→) :: Ingredient -> Double -> UsedIngredient
+(→) ingredient qtt = UsedIngredient ingredient qtt
+
 eau = Ingredient "Eau" 0.003
 savonMarseille = Ingredient "Savon de Marseille" 3.36
 bicarbonate = Ingredient "Bicarbonate de soude" 3.81
@@ -31,10 +34,10 @@ vinaigreBlanc = Ingredient "Vinaigre blanc" 0.36
 
 lessive :: Recipe
 lessive = Recipe "Lessive"
-                 [ UsedIngredient eau 2.5
-                 , UsedIngredient savonMarseille 0.1
-                 , UsedIngredient bicarbonate 0.016
-                 , UsedIngredient vinaigreBlanc 0.03
+                 [ eau → 2.5
+                 , savonMarseille → 0.1
+                 , bicarbonate → 0.016
+                 , vinaigreBlanc → 0.03
                  ]
                  2.5
                  30