Challenge 3: Lazy Evaluation on an Infinite Range — Solution

result = (1..Float::INFINITY).lazy
  .select { |n| n % 3 == 0 }
  .select { |n| n > 100 }
  .first(5)

puts result.inspect

# Without .lazy, (1..Float::INFINITY).select { ... }.select { ... } would
# try to eagerly build a complete intermediate array from EVERY number in
# the infinite range before .first(5) ever got a chance to run — since the
# range never ends, the program would simply hang forever, never reaching
# the .first(5) line at all. .lazy makes each .select only pull one value
# at a time, on demand, so .first(5) can stop the whole chain the moment
# it has collected 5 matching results.

=begin
Output:
[102, 105, 108, 111, 114]

Notes:
- .lazy converts the range into a lazy enumerator immediately, before
  either .select call runs.
- Each .select in the chain is itself lazy — it doesn't build an
  intermediate array, it just wraps the previous step with an additional
  filter condition, all evaluated lazily together.
- .first(5) is what actually triggers evaluation, pulling values through
  the whole lazy chain one at a time until 5 pass both select conditions,
  then stopping immediately — it never touches the range beyond 114.
=end