formatStmt (Pop id1 id2 _) =
  text "pop" <> parens (formatIdent id1 <> comma <+> formatIdent id2)
formatStmt (Pop id1 id2 _) =
  text "pop" <> parens (formatIdent id1 <> comma <+> formatIdent id2)
formatStmt (Pop id1 id2 _) =
  text "pop" <> parens (formatIdent id1 <> comma <+> formatIdent id2)