Circular list iterator in Python

Use itertools.cycle, that’s its exact purpose:

from itertools import cycle

lst = ['a', 'b', 'c']

pool = cycle(lst)

for item in pool:
    print item,

Output:

a b c a b c ...

(Loops forever, obviously)

In order to manually advance the iterator and pull values from it one by one, simply call next(pool):

>>> next(pool)
'a'
>>> next(pool)
'b'

Related Posts:

  1. How to iterate through two lists in parallel?
  2. How can I reverse a list in Python?
  3. Difference between del, remove, and pop on lists
  4. How can I reverse a list in Python?
  5. What is the difference between Python’s list methods append and extend?
  6. Understanding slice notation
  7. Understanding slice notation
  8. What does the “yield” keyword do?
  9. How to convert list to string [duplicate]
  10. How do I get the number of elements in a list?
  11. Finding the index of an item in a list
  12. How to make a flat list out of a list of lists
  13. Removing duplicates in lists
  14. List changes unexpectedly after assignment. Why is this and how can I prevent it?
  15. TypeError: ‘float’ object is not subscriptable
  16. Is there a short contains function for lists?
  17. TypeError: ‘float’ object is not subscriptable
  18. Transpose/Unzip Function (inverse of zip)?
  19. appending list but error ‘NoneType’ object has no attribute ‘append’
  20. Check if something is (not) in a list in Python
  21. How to avoid “RuntimeError: dictionary changed size during iteration” error?
  22. Finding the average of a list
  23. Print a list in reverse order with range()?
  24. Get unique values from a list in python [duplicate]
  25. Why is it string.join(list) instead of list.join(string)?
  26. Why is it string.join(list) instead of list.join(string)?
  27. How do I concatenate two lists in Python?
  28. if else in a list comprehension
  29. Finding median of list in Python
  30. Python set to list
  31. Python List vs. Array – when to use?
  32. How to find all occurrences of an element in a list
  33. Finding and replacing elements in a list
  34. How to find all the indexes of a recurring item in a list?
  35. ValueError: max() arg is an empty sequence
  36. Remove list from list in Python
  37. How do I concatenate two lists in Python?
  38. Replace values in list using Python
  39. Append integer to beginning of list in Python
  40. List comprehension on a nested list?
  41. Union of two lists in Python
  42. Writing a list to a file with Python
  43. Python: Get the first character of the first string in a list?
  44. Understanding slice notation
  45. How do I find the duplicates in a list and create another list with them?
  46. ‘numpy.float64’ object is not iterable
  47. Add list to set?
  48. What’s the idiomatic syntax for prepending to a short python list?
  49. How to remove an element from a list by index
  50. Apply function to each element of a list
  51. Remove all occurrences of a value from a list?
  52. Converting Dictionary to List?
  53. How to deep copy a list?
  54. TypeError: list indices must be integers or slices, not str
  55. In Python, when to use a Dictionary, List or Set?
  56. Removing Punctuation From Python List Items
  57. Check if two unordered lists are equal
  58. ‘list’ object has no attribute ‘shape’
  59. How do I find the duplicates in a list and create another list with them?
  60. How can I compare two lists in python and return matches
  61. How do I check if a list is empty?
  62. How can I get list of values from dict?
  63. IndexError: list index out of range and python
  64. AttributeError: ‘list’ object has no attribute ‘replace’ when trying to remove character
  65. How to sort a list of objects based on an attribute of the objects?
  66. AttributeError: ‘list’ object has no attribute ‘replace’ when trying to remove character
  67. How to append multiple values to a list in Python
  68. How do you split a list into evenly sized chunks?
  69. How to remove \n from a list element?
  70. How to return dictionary keys as a list in Python?
  71. How can I create an array/list of dictionaries in python?
  72. How to sort a list/tuple of lists/tuples by the element at a given index?
  73. Defining lists as global variables in Python
  74. Subtracting two lists in Python
  75. How to multiply all integers inside list
  76. Get the cartesian product of a series of lists?
  77. Python 2: AttributeError: ‘list’ object has no attribute ‘strip’
  78. What does the “x for x in” syntax mean?
  79. How to make a set of lists
  80. How to remove square brackets from list in Python?
  81. numpy-equivalent of list.pop?
  82. Difference between Python’s Generators and Iterators
  83. Create nice column output in python
  84. TypeError: only integer arrays with one element can be converted to an index 3
  85. Logical indexing with lists
  86. How does str(list) work?
  87. convert csv file to list of dictionaries
  88. Element-wise addition of 2 lists?
  89. How to split elements of a list?
  90. Find object in list that has attribute equal to some value (that meets any condition)
  91. Turn a single number into single digits Python
  92. How to create a list of objects?
  93. Iterating through list of list in Python
  94. Python cant convert ‘list’ object to str error [closed]
  95. Get difference between two lists
  96. How is Python’s List Implemented?
  97. Determine if 2 lists have the same elements, regardless of order? [duplicate]
  98. Building a list inside a list in python
  99. Sorting list based on values from another list
  100. Create a list with initial capacity in Python

Leave a Comment