(This is my first time posting on any Python list; I've tried to search for
this idea and didn't find it but if I looked in the wrong places/this has
already been discussed I apologize and feel free to tell me!)
Say you have a list and you want to perform some operation on each item in the
list - but you don't need to store the result in a list.
There are three simple ways of doing this, at least as far as I know:
([print(item)] could be any expression, just using it as an example)
```
lst = [1, 2, 3, 4]
#1
for item in lst:
print(item)
# 2
[print(item) for item in lst]
# 3
for item in lst: print(item)
```
#1 - In my opinion, this should be a one line operation so #1 is not ideal.
#2 - It also shouldn't require storing results in array, to save time/memory,
so #2 is out.
#3 - I think #3 is just not good syntax, it seems very unpythonic to me - it
breaks the norm that blocks go on their own lines. It does seem the best of the
three though and I know my assessment is kind of subjective.
I'm wondering if a possible alternative syntax could be a for-expression, like
there's if-expressions, which always evaluates to None:
```
print(item) for item in lst
```
A more practical example of when this would be useful is extending list-2 with
a modified version of list-1 - this syntax would avoid creating an intermediate
list (not sure if the way lists are implemented in python removes this
advantage by the way it resizes lists though).
```
lst1 = [1, 2, 3]
lst2 = [4, 5, 6]
lst1.append(item * 2) for item in lst1
```
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