Iterate a certain number of times without storing the iteration number anywhere

Question

I was wondering if it is possible to perform a certain number of operations without storing the loop iteration number anywhere   For instance  let s say I want to print two  hello  messages to the console  Right now I know I can do   for i in range 2       print  hello    but then the i variable is going to take the values 0 and 1  which I don t really need   Is there a way to achieve the same thing without storing those unwanted values anywhere

User · Accepted Answer

The idiom  shared by quite a few other languages  for an unused variable is a single underscore    Code analysers typically won t complain about   being unused  and programmers will instantly know it s a shortcut for i dont care wtf you put here  There is no way to iterate without having an item variable - as the Zen of Python puts it   special cases aren t special enough to break the rules

User · Answer

exec  print  hello      2   should work  but I m kind of ashamed that I thought of it   Update   Just thought of another one   for   in     10  print  hello

User · Answer

Others have addressed the inability to completely avoid an iteration variable in a for loop  but there are options to reduce the work a tiny amount  range has to generate a whole bunch of numbers after all  which involves a tiny amount of work  if you want to avoid even that  you can use itertools repeat to just get the same  ignored  value back over and over  which involves no creation retrieval of different objects   from itertools import repeat  for   in repeat None  200      Runs the loop 200 times           This will run faster in microbenchmarks than for   in range 200    but if the loop body does meaningful work  it s a drop in the bucket  And unlike multiplying some anonymous sequence for your loop iterable  repeat has only a trivial setup cost  with no memory overhead dependent on length

User · Answer

This will print  hello  3 times without storing i      print  hello   for i in range 3

User · Answer

You can simply do  print 2  hello

User · Answer

Although I agree completely with delnan s answer  it s not impossible   loop   range NUM ITERATIONS 1  while loop pop        do stuff     Note  however  that this will not work for an arbitrary list  If the first value in the list  the last one popped  does not evaluate to False  you will get another iteration and an exception on the next pass  IndexError  pop from empty list  Also  your list  loop  will be empty after the loop   Just for curiosity s sake

User · Answer

for word in   hello     2      print word   It s not idiomatic Python  but neither is what you re trying to do

User · Answer

Sorry  but in order to iterate over anything in any language  Python and English included  an index must be stored  Be it in a variable or not  Finding a way to obscure the fact that python is internally tracking the for loop won t change the fact that it is  I d recommend just leaving it as is

User · Answer

Well I think the forloop you ve provided in the question is about as good as it gets  but I want to point out that unused variables that have to be assigned can be assigned to the variable named    a convention for  discarding  the value assigned  Though the   reference will hold the value you gave it  code linters and other developers will understand you aren t using that reference  So here s an example   for   in range 2       print  Hello

[python] Iterate a certain number of times without storing the iteration number anywhere

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