Loops & Iterators

While Ruby supports standard `while` loops, idiomatic Ruby code prefers **block iterators** like `times`, `upto`, and `step`, which take closures to iterate safely and cleanly:

• `until`: Loop executes as long as a condition is **false** (opposite of while).
• `times`: Repeats a block a specific number of times: `5.times { |i| puts i }`.

Let's run a program illustrating loops, until statements, and times iterators:

# 1. Until loop (runs until condition is true)
count = 1
print "Until loop: "
until count > 5
  print "#{count} "
  count += 1
end
puts

# 2. Block-based Times iterator
print "Times iterator: "
3.times do |index|
  print "Count:#{index} "
end
puts

# 3. Upto iterator
print "Upto loop: "
1.upto(4) { |num| print "#{num} " }
puts