Strange ambiguous call error

[PMunch]

Because 56 is an undetermined int literal, it can be any int you want, even a 
float in certain situations. Nim simply hasn't decided yet what kind of int it 
is, because it doesn't know how you intend to use it. If you assign 56 to a 
variable it will work fine, because Nim now treats it as an int. And if you 
specify what kind of int it is it will work as well.