Ruby Basics - Comparison Operators
=begin Equality and Relational Operator
== Equal; see discussion below
!= Not equal
> Greater than
< Less than
>= Greater than or equal to
<= Less than or equal to
<=> Combined comparison operator.
0 if first operand equals second,
1 if first operand is greater than the second
-1 if first operand is less than the second.
=== Test equality within a when clause of a case statement.
(1...10) === 5 returns true.
.eql? True if the receiver and argument have
both the same type and equal values.
1 == 1.0 returns true, but 1.eql?(1.0) is false.
equal? True if the receiver and argument have the same object id.
if aObj is duplicate of bObj then,
aObj == bObj is true,
a.equal?bObj is false but,
a.equal?aObj is true.
=end