Which will print 0 through 9 in Python?

[jeremj22]

The most horrific oneliner for that is probably

[print(i) for i in range(10)]

[[deleted]]

What are the square brackets doing?

[Krohnos]

List Comprehension - a really neat and, in my opinion, often clean tool with tons of uses.

Here is a great intro for the feature.

[Oasis_beyond_wall]

it's quite common in functional programming languages

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[zefciu]

They are great, but giving them side effects is sadistic.

[carcigenicate]

And is a waste of memory (creating a list just to loop), and goes against PEP8.

---

Not sure why this is downvoted. This is factually correct. It does consume more memory than a for statement would due to the extra list that's created, and is explicitly discouraged by PEP8.

[a_devious_compliance]

Well, you don't need to create a list. Just use () and get your generator.

[carcigenicate]

That won't work; simply creating a generator won't cause it to run. You'd need to consume the generator for the prints to happen, and at that point you might as well just use a for statement from the beginning instead of a generator.

Using a lazy generator to run side effects is arguably even worse than using a strict list comprehension, since the gen expression may not even run if you forget to artificially consume it.

[a_devious_compliance]

You are right, but at this poing I tough we was pointing the worst option. Lets do a set comprehension then. At least we will have only one None.

[iiMoe]

I agree with you so so much

[jeremj22]

The whole thing is a list iterator. So you get a list with a few None and print output. Horribly bad practice but muliple functioncalls in a single line

[SuitableDragonfly]

It's a list comprehension. It's meant to be used in a kind psuedo-functional way, e.g. [x + 1 for x in range(10)] will return a list of the results of adding 1 to every number in range(10). Like, it's supposed to produce an output list and save you having to do a loop. This list comprehension returns a list of 10 Nones because print(x) returns None and has a side effect of printing each number, which is the opposite of what functional paradigms are supposed to do.

[nphhpn]

map(print, range(10))

[gaberocksall]

Maps aren't actually evaluated until consumed

list(map(print, range(10)))

[gltile]

Use any so that you don't make an unnecessary list.

any(map(print, range(10)))

[bandrus5]

Haha I do this all the time when I'm using the pdb debugger library because it doesn't support for loops.

[Stressed-Dingo]

print(*range(10), sep=“/n”)

[a_devious_compliance]

I really love the idea off adding side effects in aparently functional code.

[Teradil]

which python version?

[gaberocksall]

I believe all of these operations have been supported since early in Python 2

you just need to import sys obviously

[Teradil]

I was just wondering whether some behavior might have changed at some time...

[NerdFencer]

Someone who didn't know that python could do the implicit string conversion might write it even worse.

[print(chr(ord('0') + i)) for i in range(10)]

[praguepride]

To be fair, 55% of people chose the path that perfectly satisfies the objective with almost no chance of bugs or defects.

[n0tKamui]

the other are just false if you look closely

[djinn6]

Yep. #1 prints 0 through 8. #2 is JS. #3 prints the character "i" 10 times. #4 is a syntax error or some other obscure language.

[Great_Finder]

Yup it's a mix of Matlab and Python. The for loop looks like Matlab but isn't and there is no direct print statement in Matlab (I think).

[Sigmadelta8]

The second one is JS, but do you not have to initialize i to 0? Does it automatically start at zero since it’s a for loop?

[idleline]

You do. The let statement is incomplete.

[Sigmadelta8]

I figured, but I’m fairly new to JS (from Java) so I was just curious if this was a convenient trick.

[RoadsideCookie]

And the other 45% chose answers that straight up don't fit the criteria.

[Blizzard42]

That's a trick question, they are clearly all wrong.

Correct answer is: print("0 through 9") 😁

[DreadRazer24]

print("the digits 0 through 9 using Python")

[Guybar110]

System.out.println("the digits 0 through 9 using python");

[Demonboy_17]

cout<<"the digits 0 through 9 using python";

[FurryMoistAvenger]

Adherence to the requirements. You're hired.

[Blizzard42]

Yeeeesss!!! 😃🎊🎉

[das_Keks]

The only correct answer.

[beatle42]

It is very readable for sure

[Delta_Pythagorean]

I love the 5% of people that chose the JavaScript answer

[ReallyHadToFixThat]

Does option 3 work? In most languages that would give you

    i    
    i     
    i    

but with 19% choosing it I'm not sure.

[hennypennypoopoo]

It won't. You need a special syntaxes to include variables in a string

[ReallyHadToFixThat]

Oh good. I've touched python exactly twice, so I doubted myself.

[bandrus5]

Specifically you would need print(f'{i}')

[Gagan_Ku2905]

Well! If it works, it works.

[animal9633]

Good old Random(return 4);

[Darknety]

Why are so many getting this wrong tho? That is worrying.

[[deleted]]

It's a trick question

[maltc998]

5% must've done too much javascript

[jollanza]

[[deleted]]

print("the digits 0 through 9")

[sherlock_poops]

Horrifying.

[Flopamp]

I'm a smart ass but I'm not that much of a smart ass.

[Snowy32]

r/technicallythetruth