I have a question similar to 74335.
Let $R$ be an integral domain. Is there a nice description of the fraction field of the power series $R[[x]]$?
I know that this field can be a proper subfield of $\operatorname{Frac}(R)((x))$, the Laurent series over the fraction field of $R$, as seen here. Given that, I'm at a loss of other candidates for what $\operatorname{Frac}(R[[x]])$ can be.