empty<T>                                 : []
single(42)                               : [42]
iota(0,6)                                : [0, 1, 2, 3, 4, 5]
iota(0) | take(3)                        : [0, 1, 2]
repeat(6) | take(3)                      : [6, 6, 6]

counted(begin(v),size(v))                : [1, 3, 5, 4, 2]
v | all                                  : [1, 3, 5, 4, 2]
v | drop_while(below_5)                  : [5, 4, 2]
v | enumerate                            : [(0, 1), (1, 3), (2, 5), (3, 4), (4, 2)]
v | filter(below_5)                      : [1, 3, 4, 2]
v | reverse                              : [2, 4, 5, 3, 1]
v | take_while(below_5)                  : [1, 3]
v | transform(square)                    : [1, 9, 25, 16, 4]

v | chunk(3)                             : [[1, 3, 5], [4, 2]]
v | chunk_by(std::ranges::less{})        : [[1, 3, 5], [4], [2]]
v | pairwise_transform(double_digit)     : [13, 35, 54, 42]
v | pairwise                             : [(1, 3), (3, 5), (5, 4), (4, 2)]
v | slide(2)                             : [[1, 3], [3, 5], [5, 4], [4, 2]]
v | stride(2)                            : [1, 5, 2]

s                                        : ['A', 'B', ' ', 'C', 'D', 'E']
s | split(' ')                           : [['A', 'B'], ['C', 'D', 'E']]
s | split(' ') | join                    : ['A', 'B', 'C', 'D', 'E']
s | split(' ') | join_with("<>"s)        : ['A', 'B', '<', '>', 'C', 'D', 'E']

zip(v, s)                                : [(1, 'A'), (3, 'B'), (5, ' '), (4, 'C'), (2, 'D')]
zip_transform(double_digit, v, v)        : [11, 33, 55, 44, 22]
cartesian_product(v|take(2), s|take(2))  : [(1, 'A'), (1, 'B'), (3, 'A'), (3, 'B')]

m                                        : {"answer": 42, "wrong": 54}
m | keys                                 : ["answer", "wrong"]
m | values                               : [42, 54]