ruby 的equal?的一点问题

Question

a = 2; b=2; puts a.equal?(b);为甚么是true
a=1.0; b=1.0; puts a.equal?(b) 为什么是FALSE

Answer 1

Equality---At the +Object+ level, +==+ returns +true+ only if obj
and other are the same object. Typically, this method is
overridden in descendent classes to provide class-specific meaning.

Unlike +==+, the +equal?+ method should never be overridden by
subclasses: it is used to determine object identity (that is,
+a.equal?(b)+ iff +a+ is the same object as +b+).

The +eql?+ method returns +true+ if obj and anObject have the
same value. Used by +Hash+ to test members for equality. For
objects of class +Object+, +eql?+ is synonymous with +==+.
Subclasses normally continue this tradition, but there are
exceptions. +Numeric+ types, for example, perform type conversion
across +==+, but not across +eql?+, so:

1 == 1.0     #=> true
1.eql? 1.0   #=> false