Why fixnum doesn't have eigenclass?
This method is to return eigenclass of any object:
class Object
def eigenclass
class << self; self; end
end
end
Example for String:
"abc".eigenclass # => #<Class:#<String:0x331df0>>
Array:
[1, 2].eigenclass # => #<Class:#<Array:0x0000000065d218>>
But with Fixnum:
1.eigenclass # => TypeError: can't define singleton
Why?
As the Ruby Docs say:
There is effectively only one Fixnum object instance for any given integer value, so, for example, you cannot add a singleton method to a Fixnum.
The same is true for Bignum
, Float
and Symbol
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