class IndexGenerator:
    ''' A lightweight Index Generator that support multi-dimensional shapes.
    Indices are genrated on-the-fly!

    # Args:
        - shape : tuple or list.

    # Usage
    import numpy as np
    array = np.ones((32,35,3,10))
    for index IndexGenerator(array.shape):
        print(array[index])
    '''

    def __init__(self,shape):
        self.shape = shape
        self.ndim = len(shape)
        self.counters = [0] * self.ndim
        self.has_next = len(shape)>0 and not 0 in shape

    def __iter__(self):
        return self

    def __next__(self):

        if not self.has_next:
            raise StopIteration

        return self.get_next_index()

    def increment_single_index(self,index):
        if self.counters[index] < self.shape[index] - 1:
            self.counters[index] += 1
            return False
        else:
            self.counters[index] = 0
            return True

    def get_next_index(self):
        next_index = tuple(self.counters)
        dim = -1
        while dim >= -self.ndim and self.increment_single_index(dim):
            dim -= 1
        if dim < -self.ndim:
            self.has_next = False
        return next_index