From: Roger Pack <rogerpack2005@...>
Date: 2009-04-15T11:23:32+09:00
Subject: Re: a few thoughts for ruby...

> 09:41:50 ~$ ruby19 x.rb
> Float              0.00000000010000000827
> BigDecimal         0.00000000010000000000
> Float              0.00000000000000000827
> BigDecimal         0.00000000000000000000
> false
> true
> 09:41:52 ~$ cat x.rb

Good examples.
I should explain better my original thought perhaps--I don't actually 
want to convert "rounded" data but yes make it "cleaner" and "simpler" 
to make BigDecimals.
I think I can achieve this by allowing for BigDecimal(float) but, 
similar to how String#to_s works currently in trunk:
"only accept default values of floats"
i.e.

BigDecimal(0.9)
=>  #<BigDecimal:b7db9e14,'0.9E0',4(8)>

>> BigDecimal((2.0-1.1).to_s) # 2.0-1.1 != 0.9
# BOOM not allowed, since that's a float that's been rounded away from 
its pure form (0.9's default form)

You can ascertain this a la
("%g" % (2.0-1.1)).to_f != (2.0-1.1) # blow up in this case--those are 
rounded floats we don't want to convert them.

Somewhat sane?

-=r
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