> my Rational $x = 1.111111111111111111111;
1.11111111111111111604544
> $x *= 0.1;
Type check failed in assignment to $x; expected Rational but got Num (0.111111111111111e0)

##</code><code>##

> sub foo(FatRat() $x) { return $x }; foo(pi).nude
(355 113)
> pi.FatRat(1e-8).nude
(103993 33102)

##</code><code>##

> my FatRat() $x = 0.1;
===SORRY!=== Error while compiling:
Coercion FatRat(Any) is insufficiently type-like to qualify a variable
------> my FatRat() $x&#9167; = 0.1;
    expecting any of:
        constraint