[Debilski]

round(x) only works for a few specialised types of x. help(round) tells you that it will return the same type then. Of course for a type of MathConst{:π}, that won’t work. For generic types, you need to at least specify the number of digits (round(pi, 3)). (See also: methods(round))

[glomph]

Weird that they have round(pi) as an example.

[pygy_]

It may have worked at some point. The language evolves pretty quickly at the moment.