From: Adam Aa <aminaleali@...>
Date: 2010-03-02T12:08:49+09:00
Subject: Re: Is this a bug or a whole new concept?

Apologies...should have checked the documentation first..we are also 
comparing types with "eql?"

num.eql?(numeric)    => true or false
-----------------------------------------------------------------------
Returns true if num and numeric are the same type and have equal values.

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


Adam Aa wrote:
> 
> Greetings,
> 
> I got a book on Ruby and I am trying to learn it piece by piece.  I was
> a Perl programmer for a while so the syntax of Ruby is not too hard for
> me.  What I don't understand is the following and I thank you in advance
> for your help and input.
> 
> I have a variable named "num" that is set to "9."  I'm using the
> num.eql?() method to test whether or not num.eql?(9) and it gives me
> "true" in IRB - no surprise there.  The next one below also gives me
> "true" since 18/2 is 9.  I read in the book that if you want to force
> the result of an experssion to be a float, make one or both operands a
> floating number. So we have 18/2.0. But the result is "false." How come?
> How come everytime I change either the number to float I get a false
> even though the expression is correct?  At first I thought I'm not
> dividing numbers - rather maybe I'm dividing the value of the chars
> rather than their math value.  But that's not true as "18.to_i/2.to_i,"
> just like "18/2," gives us "true."
> 
> I'm all ears to hear the logic behind such behavior
> 
> Thanks again
> 
> irb(main):058:0> num.eql?(9)
> => true
> irb(main):059:0> num.eql?(18/2)
> => true
> irb(main):060:0> num.eql?(18/2.0)
> => false
> irb(main):061:0> num.eql?(18.0/2)
> => false
> irb(main):062:0> num.eql?(18.0/2.0)
> => false
> irb(main):063:0> num.eql?(18/2)
> => true
> irb(main):064:0> num.eql?(18.0/2.to_f)
> => false
> irb(main):065:0> num.eql?(18.to_f/2.to_f)
> => false
> irb(main):066:0> num.eql?(18.to_f/2.to_i)
> => false
> irb(main):067:0> num.eql?(18.to_i/2.to_i)
> => true
> irb(main):068:0>

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