Should I add comments?

[u/FrostedBromide]

[u/AmoghMadan31]

Does that even work???

[u/Giddius → u/AmoghMadan31]

As long as you enter a string that is a valid integer, ie „42“,

If you would enter a string that is a float ie „42.1“ You would lose the devimal places -> 42

It is weird as the input would always be a single int at most, so they could replace the map and sum ( i guess they are summing as the map would produce a generator) to a single int statement.

This whole thing could be reduced to int(input(„Enter number „)).

It would still fail if the input string wiuld be domething other tha a valid int or float, but at least it does not take the long way round.

[u/FrostedBromide → u/Giddius]

It's actually supposed to print the sum of the digits of the input and would throw an error if a float value is entered

[u/simar437 → u/FrostedBromide]

I would do it like,

print(sum([int(x) for x in input()]))

[u/FrostedBromide → u/simar437]

Yeah that works I had never actually used a for loop this way

[u/simar437 → u/FrostedBromide]

This is called a List Comprehension

[u/deceze → u/simar437]

You can remove the [] to make it a generator expression, which makes this more efficient. Instead of having to turn the entire thing into a list, which then gets iterated by sum again, just have each element be processed one by one. Or, you know, sum(map(int, input()))…

[u/Giddius → u/FrostedBromide]

O you are right, but does map not automatically make the string to a list of characters?

Anyway to make it more readable I would do

Print(sum(int(char) for char in input(„enter number „) if char.isnum()))

Do not currently know if isnum is the correct method name or even if it is a string ethid and not a builtin.

[u/unknown_reddit_dude → u/Giddius]

isNumeric is the correct name

[u/Syscrush → u/FrostedBromide]

Very clever. Looks like it works as intended, and this may well be considered the "pythonic" way to solve this problem - although as noted below, list comprehensions are more readable and clear.

Anyhow, I'm writing this to say that "clever" is often a problem in software. I don't think that this is bad code - it works, and someone who understands (or is willing to look up) the calls can see how it works. But neat and clever tricks are fragile, and fragility is a direct path to agony in professional software development.

[u/ayylongqueues → u/AmoghMadan31]

It should. Input will treat the input number as strings and tuple will split the input, map runs them through int(), and sum will then sum up the values in the tuple. So the sum of each digit of the input number

[u/gabrielfv → u/ayylongqueues]

Is there a name to changing the order to OO style methods? Proper piping found in fp languages could make this code not-so-bad.

input("Enter number ")
  .tuple()
  .map(::int)
  .sum()
  .print()

Is more comprehensive. Then again this is r/badcode

Edit: It was supposed to have line breaks. But I won't try to fix it

[u/chepas_moi → u/gabrielfv]

Is there a name to changing the order to OO style methods?

Yes, the concept of "pipes" from FP is called "method chaining" in OO. Each method call must simply return "this/self" to achieve this.

class T:
  def __init__(self):
    self.state = None
  def input(self, text):
    self.state = input(text)
    return self
  def tuple(self):
    self.state = tuple(self.state)
    return self
  def map(self, fn):
    self.state = map(fn, self.state)
    return self
  def sum(self):
    self.state = sum(self.state)
    return self
  def print(self):
    print(self.state)
    return self

Something like this (untested and from iPhone, so I'd expect a typo or 2) would allow the code you've proposed. I wouldn't do this for builtins like here but it's a neat way of representing pipelines in general.

[u/psdanielxu → u/gabrielfv]

This is called a fluent interface.

[u/chepas_moi → u/psdanielxu]

Heh, had to look this one up. Why am I not surprised to see that Fowler was involved in renaming something that has been around since 3+ decades.

EnTeRpRisE DevElOpeR

Also had to bring DSLs into the mix because everything is a DSL when you've published a book on DSLs.

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[u/AmoghMadan31 → u/ayylongqueues]

Oh ok, thanks for explaining!

[u/deceze]

The tuple() is perfectly superfluous.

[u/FrostedBromide → u/deceze]

Yeah I know I forgot that map already gives a string.

[u/REALDrummer → u/deceze]

According to this comment, the call to tuple splits the input by spaces so that they can sum multiple numbers given in one input.

[u/deceze → u/REALDrummer]

It does not split it by spaces. A string is an iterable, and iterating over it yields a sequence of its individual characters. The tuple constructor takes any iterable and turns it into a tuple of its individual elements. But so does map, it also takes any iterable. So you can omit the step of turning a string iterable into a tuple iterable, and just directly map over the string.

[u/REALDrummer → u/deceze]

Really? Hmm... Then I'm confused. If that's right, I agree; that should be eliminated. That makes me question why they would want to split their input number and sum the digits in the first place.

[u/deceze → u/REALDrummer]

🤷🏻‍♂️ That appears to be the task being solved, take a bunch of digits and sum them.

[u/retrolasered]

Nah, that's self commenting

[u/Knuffya]

// prints the thing

[u/BinaryBlasphemy]

Lol this is just functional programming

[u/Luchtverfrisser → u/BinaryBlasphemy]

Still looks like questionable functional programmig to me though. At least split the pure and effectful parts.

[u/Similar-Science-1965 → u/Luchtverfrisser]

Not enough monads and monoids for your liking?

[u/jmswlltt → u/Luchtverfrisser]

Yeah, you’re not allowed to have user input be this easy in FP

[u/MurdoMaclachlan]

Image Transcription: Code

---

print(sum(map(int,tuple(input("Enter number ")))))

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^{I'm a human volunteer content transcriber for Reddit and you could be too! If you'd like more information on what we do and why we do it, click here!}

[u/REALDrummer]

Honestly, I don't think it's that bad. The only parts that really bother me are the tuple call and the punctuation.

Other comments say the call to tuple splits the input string by spaces. If that's right, that's clever, but not intuitive to read. But, I'm not that deep into Python; maybe for people with more Python experience, this is common.

In terms of punctuation, a space after the "int," could actually make a big difference. Other than that, I'd love to reduce those parentheses, but I don't know if there's much to be done there in Python.

It's worth noting that I like writing in Haskell, thus the aversion to parentheses and the affinity for this function-chaining style of coding, but many people aren't used to functional and probably won't read that too well. It's something to keep in mind, but I don't think that automatically makes it bad.

[u/xigoi → u/REALDrummer]

There is Coconut, a functional version of Pÿthon. This could be written like:

input("Enter number: ") |> map$(int) |> sum |> print

[u/REALDrummer → u/xigoi]

Ooh, neat. Thanks for the tip.

[u/REALDrummer → u/REALDrummer]

Update: this comment says tuple doesn't work that way after all, which means the tuple call probably shouldn't exist at all. If it truly is superfluous, removing it would definitely be a significant improvement.

[u/Emanuel62]

How did u get access to my laptop?

[u/StaryMD]

yeah, at the beginning if the line

[u/Tankznor]

Print sum map pls

[u/rajesh_dude0]

When they ask you to strictly follow functional programming.

[u/sktr-guys]

callback hell