http://www.perlmonks.org?node_id=11137452

hi rob, from the docs we have:

Coerces both arguments to Numeric (if necessary); returns True if they are equal.
```> my \$x = 1/10;   #0.1
> \$x.^name;       #Rat

> my  \$y = 3602879701896397/36028797018963968;   #0.100000000000000006
> \$y.^name;       #Rat

> \$x == \$y         #False   (no coercion necessary)
> \$x == 0.1        #True     (no coercion necessary)
> \$y == 0.1        #False   (no coercion necessary)
so comparing without coercion works as you expect

> 0.1e0.^name;  #Num
> \$x == 0.1e0    #True    (coerces \$x to Num, then compares)
> \$y == 0.1e0    #True    (coerces \$y to Num, then compares)

coercion from Rat to Num can result in loss of precision
> say \$y.nude   #(3602879701896397 36028797018963968)
> say \$y.Num    #0.1
coercing this particular Rat to a Num collapses it to 0.1
IIRC the limit of Rat precision is e-14 ish (it gets lumpy),
so in the general case it is fair to round away your ...00006 to 0
thus the Num 0.1 maps to both of these Rat options
[download]```

your python example does much the same...

print (Fraction(3602879701896397, 36028797018963968) == 0.1); # True