minim_shift_register.py

class Shifting:
    """minimalistic shifting register"""
    point = 0
    def __init__(self,el,how_m):
        """el -- first element to add
        how_m -- length of shifting register
        """
        self.lis = [el for ii in range(how_m)] # we start with multiplying first element
        self.how_m = how_m

    
        
        
        
    def give_elements(self):

        nn = 0
        for el in self.lis[self.point:]:
            if nn<self.how_m:
                yield el
            else:
                break
            nn+=1
        for el in self.lis[0:self.point]:
            if nn<self.how_m:
                yield el
            
            else:
                break
            nn+=1
            
    def add_element(self,el):
        self.lis[self.point] = el
        self.point +=1
        self.point = self.point %self.how_m
       
#usage

#shif = Shifting(1,21)

#for el in range(21):
#    shif.add_element(el)

#print(list(shif.give_elements()))