Inserting a \circ inside a minted block [duplicate]

Question

I'm trying to insert a \circ inside a minted block of code, to emit the following: g ∘ f:

\begin{minted}[escapeinside=||]{haskell}
g |\circ| f
\end{minted}

I was trying to follow the minted documentation, and attempted to do it inside a escapeinside, but without much success, I get an error:

<inserted text>
                $
l.2 \PYG{n+nf}{g} \PYG{esc}{\circ} \PYG{n}{f}
...

Am I holding it wrong? Is there a better way?