i2encapsulation

greatabel · greatabel · commit 75c208cdeca2 · 2018-06-24T22:02:16.000+08:00
diff --git a/Modular-Programming-with-Python/ch5Working with Module Patterns/i2encapsulation/recipes.py b/Modular-Programming-with-Python/ch5Working with Module Patterns/i2encapsulation/recipes.py
@@ -0,0 +1,67 @@
+# recipes.py
+#
+# This module demonstrate the concept of encapsulation within a Python module.
+
+def new(name, num_servings):
+    """ Create and return a new recipe.
+    """
+    return {'name'         : name,
+            'num_servings' : num_servings,
+            'instructions' : [],
+            'ingredients'  : []}
+
+
+def add_instruction(recipe, instruction):
+    """ Add an instruction to the recipe.
+    """
+    recipe['instructions'].append(instruction)
+
+
+def add_ingredient(recipe, ingredient, amount, units):
+    """ Add an ingredient to the recipe.
+    """
+    recipe['ingredients'].append({'ingredient' : ingredient,
+                                  'amount'     : amount,
+                                  'units'      : units})
+
+
+def get_name(recipe):
+    return recipe['name']
+
+
+def get_num_servings(recipe):
+    return recipe['num_servings']
+
+
+def get_instructions(recipe):
+    return recipe['instructions']
+
+
+def get_ingredients(recipe):
+    return recipe['ingredients']
+
+
+def to_string(recipe, num_servings):
+    """ Return a list of strings with a description of this recipe.
+
+        The recipe will be customized for the given number of servings.
+    """
+    s = []
+    s.append("Recipe for {}, {} servings:".format(recipe['name'],
+                                                  num_servings))
+    s.append("")
+    s.append("Ingredients:")
+    s.append("")
+    for ingredient in recipe['ingredients']:
+        s.append("    {} - {} {}".format(ingredient['ingredient'],
+                                         ingredient['amount'] * num_servings /
+                                         recipe['num_servings'],
+                                         ingredient['units']))
+    s.append("")
+    s.append("Instructions:")
+    s.append("")
+    for i,instruction in enumerate(recipe['instructions']):
+        s.append("{}. {}".format(i+1, instruction))
+
+    return s
+
