[ BeginEnv "proposition"
, Label "mathrel_notation_test"
, Word "if"
, BeginEnv "math"
, Variable "x"
, Command "mathrel"
, InvisibleBraceL
, Variable "R"
, InvisibleBraceR
, Variable "y"
, EndEnv "math"
, Symbol ","
, Word "then"
, BeginEnv "math"
, Variable "x"
, Command "mathrel"
, InvisibleBraceL
, Variable "R"
, InvisibleBraceR
, Variable "y"
, EndEnv "math"
, Symbol "."
, EndEnv "proposition"
]