Ruby/Range/Range include

print "R is within A to Z!" if ("A".."Z").include?("r")

c = -2..2
c.all? {|x| x>0}    # => false: not all values are > 0
c.any? {|x| x>0}    # => true: some values are > 0
c.none? {|x| x>2}   # => true: no values are > 2
c.one? {|x| x>0}    # => false: more than one value is > 0
c.one? {|x| x>2}    # => false: no values are > 2
c.one? {|x| x==2}   # => true: one value == 2
[1, 2, 3].all?      # => true: no values are nil or false
[nil, false].any?   # => false: no true values
[].none?            # => true: no non-false, non-nil values

(1...25) === 25 # => false, out of range if ... used

(1..25) === 14 # => true, in range
(1..25) === 26 # => false, out of range

puts   (1..10)    === 5
puts   (1..10)    === 15
puts (1..10)    === 3.14159
puts   ("a".."j") === "c"
puts   ("a".."j") === "z"

  while line = gets
    puts line if line =~ /start/ .. line =~ /end/
  end
  while gets
    print if /start/../end/
  end

print "R is within A to Z!" if ("A".."Z").include?("R")