🥥 👨🏿‍💼 🎅 Generators for the little ones 🔠 👩🏼‍🔧 🥨

Hello everyone! When I was studying Python on my own, I found enough theoretical material about the language and its capabilities. However, even after reading several articles on various sites and books, a lot did not fit in my head (yes, I'm so tight). I had to cram in incomprehensible concepts "on faith" without deep understanding, because practical examples in the articles were difficult for me. Time passed, I became more experienced, understanding came on practical problems, and at some point I began to teach my friends Python. Through mentoring, I have found that I seem to have charted a path in which complex concepts can be explained in simple terms.

With respect to the entire IT community on Children's Day and in the hope that I can help beginners understand the beauty and benefits of things that are difficult and incomprehensible at first glance, I am writing my debut article.

Today I want to talk about generators again. So, into battle!

Let's figure out the concepts and set the task

The first thing to always keep in mind when someone talks to you about Python generators is not to confuse "comprehensions" and "iterator generators". The former is powerful syntactic sugar for generating collections on the fly, the latter is a way to retrieve values on demand. Today we will focus on the second.

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def skat(n): 
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    #     range,   range  -.
    res = []
    cnt = 0
    while cnt < n:
        res.append(cnt)
        cnt += 1
    return res

def first_eater(eda_list): 
""" """ 
    for eda in eda_list: 
        print(f"   {eda}  : ", str(eda)) 
      
      
def second_eater(eda_list): 
""" """ 
    for eda in eda_list: 
        print(f"   {eda}  : ", str(eda) * 4) 
      
      
def third_eater(eda_list): 
""" """ 
    for eda in eda_list: 
        print(f"   {eda}  : ", str(eda) * 10)
      
      
#  
eda_list = skat(100_000_000) 
#   
golod_1 = 2 
golod_2 = 3 
golod_3 = 4 
# 
first_eater(eda_list[:golod_1])
second_eater(eda_list[golod_1:golod_2 + golod_1])
third_eater(eda_list[golod_2 + golod_1:golod_2 + golod_1 + golod_3])

# ,     :
# >>>    0  :  0
# >>>    1  :  1
# >>>    2  :  2222
# >>>    3  :  3333
# >>>    4  :  4444
# >>>    5  :  5555555555
# >>>    6  :  6666666666
# >>>    7  :  7777777777
# >>>    8  :  8888888888

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print(my_func_1)
print(my_func_2)

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# >>> <function my_func_1 at 0x10c399950>
# >>> <function my_func_2 at 0x10c3a4290>

, my_func_1

my_func_2

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print(my_func_1())
print(my_func_2())

# ,     
# >>>   
# >>> 1
# >>> <generator object my_func_2 at 0x108a702d0>

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def my_func_2():
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    print("   ") 
    yield 2 
    print("  !")

#     :
gen_o = my_func_2() #          generator-object

print(next(gen_o))
print(",       -  !") 
print(next(gen_o))

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print(next(gen_o))
print(next(gen_o))

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# >>> ,       -  !
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# >>> File "<  >", line 13, in <module>
# >>> print(next(gen_o))
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def skat(n):
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        0  n"""
    cnt = 0
    while cnt < n:
        yield cnt
        cnt += 1


def first_eater(golod, skat):
    """ """
    while golod > 0:
        eda = next(skat)
        print(f"   {eda}    : ", eda)
        golod -= 1


def second_eater(golod, skat):
    """ """
    eda = next(skat)
    while golod > 0:
        print(f"   {eda}    : ", str(eda) * 4)
        golod -= 1


def third_eater(golod, skat):
    """ """
    eda = next(skat)
    while golod > 0:
        print(f"   {eda}    : ", str(eda) * 10)
        golod -= 1


skat_gen_obj = skat(100_000_000)
golod_1 = 2
golod_2 = 3
golod_3 = 4

try:
    first_eater(golod_1, skat_gen_obj)
    second_eater(golod_2, skat_gen_obj)
    third_eater(golod_3, skat_gen_obj)
except StopIteration:
    print("   !")

# ,     :
# >>>    0    :  0
# >>>    1    :  1
# >>>    2    :  2222
# >>>    2    :  2222
# >>>    2    :  2222
# >>>    3    :  3333333333
# >>>    3    :  3333333333
# >>>    3    :  3333333333
# >>>    3    :  3333333333

try - except

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Generators for the little ones

Let's figure out the concepts and set the task

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