I FINALLY comprehend list comprehensions.
I can write an unlimited amount of nested loops on a single line and make other less experienced people hate me for fun and profit.

Also learned about map() #I hate it#, zip(which is awesome), and the utility of lambdas (they're okay).

Enumerate is pretty nifty too, only thing I lose is setting the initial value of the iterator index.

I was searching list comprehensions about 10 years ago (damn it has been a while) on Google. The Google search opened up like it was 3D and invited me to apply to work there. Apparently this was a way to garner interest of people who were searching for "advanced" (?, no idea) programming concepts. It happened twice and it always python list and dictionary comprehensions.

lol, map() became one of the most important tools in my tool-belt in the past decade or so.

It just transforms a list of elements from one kind into another without the bullshit of "for" loops.

How can you hate it? 😂

List and map comprehensions are awesome, map is awesome, zip is awesome, the entire intertools package is awesome

Just because juniors exist doesn't mean we have to avoid 30% of the language

@Wisecrack i thought you were smarter than me :( this is baby stuff

@Lensflare map is just a particular case of reduce. Now I mostly use reduce tbh

Haha, you just mean [not_horse for animol in stable if animol.kind in ["pony","sheep"] and animal.is_alive]? Heh, nice.

@chatgpt how to comprehend list comprehensions?

@retoor
List comprehensions in Python are a concise way to create lists based on existing lists or other iterable objects. They consist of an expression followed by a for clause, and possibly multiple for or if clauses.

Here's a general template for a list comprehension:

new_list = [expression for item in iterable if condition]

In this template:
- 'expression' is the output you want to generate for each item in the iterable.
- 'item' is the variable that represents each item in the iterable.
- 'iterable' is the object you are iterating over.
- 'condition' is an optional filter that only includes items where the condition evaluates to True.

For example, let's say you have a list of numbers and you want to create a new list containing only the even numbers from the original list. You can do this using a list comprehension:

original_list = [1, 2, 3, 4, 5, 6, 7, 8, 9]
even_numbers = [num for num in original_list if num % 2 == 0]

After executing this code, the list 'even_numbers' will

contain [2, 4, 6, 8].

List comprehensions are a powerful and efficient way to manipulate data in Python and are especially useful when you want to create a new list based on a condition or transformation applied to an existing list.

We must go deeper!

https://geeksforgeeks.org/nested-li...

@antigermgerm in some areas I am smarter. Definitely not programming though.

I've been coding with raw loops this entire time because for the longest time I just couldn't seem to grok fp.

Now I do and oh my god why the fuck would I ever go back.

Now do a walrus operator!

@JsonBoa a...what?

@Wisecrack the walrus operator - a twisted thing from the depths of a twisted mind.
Behold!
(Look for the " := " that someone thinks looks like the face of a walrus laying on its side)

```
def square(val):
return val**2

odd_squares = [
sqr
for val in range(10)
if (sqr := square(val)) % 2 != 0
]
```

@JsonBoa the walrus operator pales in comparison to the Elvis operator :)

@Lensflare I had never seen the ternary operator called "the Elvis operator". But now I can't unsee it.
Although kids nowadays will most likely call it by the name of some Bollywood bloke.