Python _ call _ Function

 

_ Call __

There is an interesting syntax in Python. This type becomes callable when the _ call _ function is implemented when the type is defined.

In other words, we can use this type of object as a function, which is equivalent to overloading the brackets operator.

Class g_dpm (object ):

Def _ init _ (self, G ):

Self. G = G

Def _ call _ (self, T ):

Return (self. g * t ** 2)/2

When computing Earth scenarios, we can set e_dpm = g_dpm (9.8), S = e_dpm (t ).

 

1.    
      
   
       
       
   class Animal(object):
       
       
    def __init__(self, name, legs):
       
       
    self.name = name
       
       
    self.legs = legs
       
       
    self.stomach = [] 
       
       
    
       
       
    def __call__(self,food):
       
       
    self.stomach.append(food)
       
       
    
       
       
    def poop(self):
       
       
    if len(self.stomach) > 0:
       
       
    return self.stomach.pop(0)
       
       
    
       
       
    def __str__(self): 
       
       
    return 'A animal named %s' % (self.name) 
       
       
    
       
       
   cow = Animal('king', 4) #We make a cow
       
       
   dog = Animal('flopp', 4) #We can make many animals
       
       
   print 'We have 2 animales a cow name %s and dog named %s,both have %s legs' % (cow.name, dog.name, cow.legs)
       
       
   print cow #here __str__ metod work
       
       
    
       
       
   #We give food to cow
       
       
   cow('gras')
       
       
   print cow.stomach
       
       
    
       
       
   #We give food to dog
       
       
   dog('bone')
       
       
   dog('beef')
       
       
   print dog.stomach
       
       
    
       
       
   #What comes inn most come out
       
       
   print cow.poop()
       
       
   print cow.stomach #Empty stomach
       
       
    
       
       
   '''-->output
       
       
   We have 2 animales a cow name king and dog named flopp,both have 4 legs
       
       
   A animal named king
       
       
   ['gras']
       
       
   ['bone', 'beef']
       
       
   gras
       
       
   []
       
       
   '''