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Python, the elegant cat in the programming language world: independent, sophisticated, and seemingly doesn’t need you until it really does. This quality is most vividly reflected in its for loop, which can make you feel like both a genius and an idiot in an instant.
It’s not that Python’s for loop is bad, it’s just that it’s too good at pretending to know better than you.
For loops in most programming languages are intuitive. Want to count to 10? No problem, give you a bunch of boilerplate code to make you feel smart.
How to write in C language:
<code class="language-c">for (int i = 0; i < 10; i++) { printf("%d\n", i); }</code>
Simple, predictable, and respectful of your IQ.
And Python says:
"Why go to the trouble of defining i, specifying a range, or doing basic arithmetic? I'll lay it all out in front of you so you can experience what it's like to be a fake programmer."
Python version:
<code class="language-python">for i in range(10): print(i)</code>
That’s it. No declarations, no braces, just "vibe". Python’s for loop is so simple that it feels a little wrong.
Suppose you have a list of fruits and want to print it out.
C language version (again, very respectful):
<code class="language-c">char* fruits[] = {"apple", "banana", "cherry"}; for (int i = 0; i < 3; i++) { printf("%s\n", fruits[i]); }</code>
Python version:
<code class="language-python">fruits = ["apple", "banana", "cherry"] for fruit in fruits: print(fruit)</code>
Did you notice anything? Python doesn't even bother to give you index. It just throws the entire element at you like a Frisbee and says, "Here, take care of it."
Do you want to show your ingenuity by manually indexing a list? What a shame. Python already knows what you want and feeds it to you directly.
Python's list comprehension is the grave of for loops.
Want to create a new list where every number is doubled? In any other language this would take 3 to 4 lines of code. Python easily demonstrates its one-line coding skills:
<code class="language-python">doubled = [x * 2 for x in range(10)]</code>
Not only is this efficient, it also makes you feel like you are writing code in some secret programming language that mere mortals will never understand. But the cost is: Your for loop now looks like a cryptic crossword puzzle.
Example:
<code class="language-python">results = [f"Employee-{i}" for i in range(10) if i % 2 == 0]</code>
Congratulations! You just wrote a line of code and two weeks later you don’t even know what it means.
Python’s for loop also likes to betray you in subtle ways. This is a classic mistake:
Unexpected variable override
<code class="language-c">for (int i = 0; i < 10; i++) { printf("%d\n", i); }</code>
Wait, what? Didn’t we replace everything with “pineapple”? No! Python is snickering in the corner because fruit
is just a temporary variable. The actual list is not modified.
Meanwhile, JavaScript developers are chuckling to themselves because they know they can bring down entire production systems with variable scope issues.
Sometimes you need both an index and a value. Python could have made you use boring i
like other languages. But it gives you enumerate(), which sounds more like a corporate term than a programming function.
<code class="language-python">for i in range(10): print(i)</code>
"enumerate". Really? Python, this is not a board meeting. Just relax.
Want to modify a list while looping through it? Python will look at you blankly and say:
"You're overthinking."
Example:
<code class="language-c">char* fruits[] = {"apple", "banana", "cherry"}; for (int i = 0; i < 3; i++) { printf("%s\n", fruits[i]); }</code>
There are now missing elements in the list because Python got lost along the way. If Python were a waiter, this would be the equivalent of clearing your table before you even finish your meal.
Try writing a classic infinite loop in Python. You know, for fun. The following is how to write it in C language:
<code class="language-python">fruits = ["apple", "banana", "cherry"] for fruit in fruits: print(fruit)</code>
The following is the Python version:
<code class="language-python">doubled = [x * 2 for x in range(10)]</code>
It does work, but it feels weird. Python doesn't even try to emulate a classic infinite loop. It's just an...infinite truth.
Conclusion: Python’s for loop is not bad - It’s just us who can’t do it
The truth is, Python’s for loop is not that bad. It’s just that we ourselves are spoiled. Python's loops are so intuitive, concise, and powerful that we forget the pain of manually tracking indexes or dealing with segfaults.
So, the next time you complain about Python’s for loops, remember this: Python is not terrible. It's just tired of holding your hand.
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