def __init__(self, capacity):
"""
Construct a Skewer instance.
:param capacity: the maximum number of items it can hold
:exception SkewerException: a capacity less than 1 was specified.
"""
if capacity < 1:
raise SkewerException("Cannot create skewer!")
self.top = None
self.cap = capacity
self.ui = SkewerUI(self.cap)
def skewer_create(capacity):
"""
Create a new empty skewer.
:param capacity (int): the maximum number of items it can hold
:exception SkewerException: a capacity less than 1 was specified.
"""
if capacity < 1:
raise SkewerException("Cannot create skewer!")
return Skewer(top=None, capacity=capacity, ui=SkewerUI(capacity))
class Skewer:
"""
Class: Skewer
Description: This class receives commands from Kabob and
works with the KebabSpot class to represent a shish-kabob
of food items on a skewer.
"""
__slots__ = "top", "cap", "ui"
def __init__(self, capacity):
"""
Construct a Skewer instance.
:param capacity: the maximum number of items it can hold
:exception SkewerException: a capacity less than 1 was specified.
"""
if capacity < 1:
raise SkewerException("Cannot create skewer!")
self.top = None
self.cap = capacity
self.ui = SkewerUI(self.cap)
def add(self, name):
"""
Add a food item to the skewer
:param name: the string name of the food item
:exception SkewerException: item could not be added.
:return None
"""
if not self.top or self.top.size() < self.cap:
self.top = KebabSpot( Food(name), self.top )
self.ui.add(self.top)
else:
raise SkewerException("Cannot add item to a full skewer!")
def front(self):
"""
Gets the name of the front item on the skewer.
:exception SkewerException: no item was on the skewer
:return the name of the food item (string) on the front
"""
if not self.top or self.size() == 0:
raise SkewerException("Cannot get item from an empty skewer!")
return self.top.get_item().name
def remove(self):
"""
Remove the front item from the skewer.
:exception: SkewerException: no item was on the skewer
:return None
"""
if not self.top or self.size() == 0:
raise SkewerException("Cannot get item from an empty skewer!")
self.ui.remove()
self.top = self.top.next
def size(self):
"""
Get the number of elements on the skewer.
:return the number of elements (int)
"""
if not self.top:
return 0
else:
return self.top.size()
def capacity(self):
"""
Get the maximum capacity of the skewer.
:return the capacity (int)
"""
return self.cap
def close(self):
"""
On destruction, close the graphical window.
:return None
"""
self.ui.close()
def is_vegan( self ):
"""
Are there only vegetables on the skewer?
:return True if there are only veggies on the skewer, False if not
"""
if not self.top:
return True
else:
return self.top.is_vegan()
def has(self, name):
"""
Is a particular food item on the skewer?
:param name: the name (string) of the food item to search for
:return True if the item is on the skewer, False if not.
"""
if not self.top:
return False
else:
return self.top.has( name )
def __str__( self ):
"""
Print a string representation of the items on the skewer.
:return A string containing all the items on the skewer, from front
to back, comma separated, and surrounded with square brackets
"""
if self.top:
return "[ " + self.top.string_em() + " ]"
else:
return "[]"