ES
Compares the two dates and returns -1, zero, 1 or nil. The other should be a date object or a numeric value as an astronomical Julian day number.
Date.new(2001,2,3) <=> Date.new(2001,2,4) #=> -1
Date.new(2001,2,3) <=> Date.new(2001,2,3) #=> 0
Date.new(2001,2,3) <=> Date.new(2001,2,2) #=> 1
Date.new(2001,2,3) <=> Object.new #=> nil
Date.new(2001,2,3) <=> Rational(4903887,2)#=> 0
See also Comparable.
Date.new(2001,2,3) <=> Date.new(2001,2,4) #=> -1
Date.new(2001,2,3) <=> Date.new(2001,2,3) #=> 0
Date.new(2001,2,3) <=> Date.new(2001,2,2) #=> 1
Date.new(2001,2,3) <=> Object.new #=> nil
Date.new(2001,2,3) <=> Rational(4903887,2)#=> 0
See also Comparable.