[ BlockLemma
    ( SourcePos
        { sourceName = "test/examples/relation-notation.tex"
        , sourceLine = Pos 1
        , sourceColumn = Pos 1
        }
    )
    ( Marker "mathrel_notation_test" )
    ( Lemma []
        ( Connected Implication
            ( TermSymbol
                ( SymbolPredicate
                    ( PredicateRelation
                        ( Command "in" )
                    )
                )
                [ TermSymbol
                    ( SymbolMixfix
                        [ Just
                            ( Command "pair" )
                        , Just InvisibleBraceL
                        , Nothing
                        , Just InvisibleBraceR
                        , Just InvisibleBraceL
                        , Nothing
                        , Just InvisibleBraceR
                        ]
                    )
                    [ TermVar
                        ( NamedVar "x" )
                    , TermVar
                        ( NamedVar "y" )
                    ]
                , TermVar
                    ( NamedVar "R" )
                ]
            )
            ( TermSymbol
                ( SymbolPredicate
                    ( PredicateRelation
                        ( Command "in" )
                    )
                )
                [ TermSymbol
                    ( SymbolMixfix
                        [ Just
                            ( Command "pair" )
                        , Just InvisibleBraceL
                        , Nothing
                        , Just InvisibleBraceR
                        , Just InvisibleBraceL
                        , Nothing
                        , Just InvisibleBraceR
                        ]
                    )
                    [ TermVar
                        ( NamedVar "x" )
                    , TermVar
                        ( NamedVar "y" )
                    ]
                , TermVar
                    ( NamedVar "R" )
                ]
            )
        )
    )
]