Ruby Comparison Operators

Last update on August 13 2023 12:00:05 (UTC/GMT +8 hours)

Comparison Operators

Comparison operators take simple values (numbers or strings) as arguments and used to check for equality between two values. Ruby provides following comparison operators :

Operator	Name	Example	Result
==	Equal	x==y	True if x is exactly equal to y.
!=	Not equal	x!=y	True if x is exactly not equal to y.
>	Greater than	x>y	True if x is greater than y.
<	Less than	x<y	True if x is less than y.
>=	Greater than or equal to	x>=y	True if x is greater than or equal to y.
<=	Less than or equal to	x<=y	True if x is less than or equal to y.
<=>	Combined comparison operator.	x<=>y	x <=> y : = if x < y then return -1 if x =y then return 0 if x > y then return 1 if x and y are not comparable then return nil
===	Test equality	x===y	(10...20) === 9 return false.
.eql?	True if two values are equal and of the same type	x.eql? y	1 == 1.0 #=> true 1.eql? 1.0 #=> false
equal?	True if two things are same object.	obj1.equal?obj2	val = 10 => 10 val.equal?(10) => true

Example: Equality test

puts ("Test two numbers for equality with ==, !=, or <=>")
 puts 14 == 16
 puts 14 != 16
 puts 14 <=> 14
 puts 14 <=> 12
 puts 14 <=> 16

Output:

Test two numbers for equality with ==, !=, or <=>
false
true
0
1
-1

Example: eql? and eqlity? operators

irb(main):023:0> 1 == 1.0
=> true
irb(main):024:0> 1.eql?1.0
=> false
irb(main):025:0> obj1 = "123"
=> "123"
irb(main):026:0> obj2 = obj1.dup
=> "123"
irb(main):027:0> obj1 == obj2
=> true
irb(main):028:0> obj1.equal?obj2
=> false
irb(main):029:0> obj1.equal?obj1
=> true
irb(main):030:0>

Example: Equal, less than, or greater than each other

puts ("Test if two numbers are equal, less than, or greater than each other")
puts 14 < 16      
puts 14 < 14
puts 14 <= 14     
puts 14.0 > 12.5
puts 14.0 >= 14

Output:

Test if two numbers are equal, less than, or greater than each other
true
false
true
true
true

Example: Spaceship operator returns -1, 0, or 1

puts ("the <=> (spaceship operator) returns -1, 0, or 1,")
puts 2 <=> 3
puts 2 <=> 2
puts 3 <=> 2

Output:

the <=> (spaceship operator) returns -1, 0, or 1,
-1
0
1

Example: Test the value in a range

puts ("test if a value is in a range")
puts (12...16) === 8
puts (12...16) === 14
puts (12...16) === 16
puts (12...14) === 12
puts (12...16) === 14

Output:

test if a value is in a range
false
true
false
true
true

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