texmath-0.13.1.2: test/writer/eqn/mfencedBseparators8.test

<<< native
[ EDelimited
    "("
    ")"
    [ Right
        (EGrouped
           [ ESub (EIdentifier "a") (ENumber "1")
           , ESymbol Pun ","
           , ESub (EIdentifier "a") (ENumber "2")
           , ESymbol Pun ","
           , ESub (EIdentifier "a") (ENumber "3")
           ])
    ]
]
>>> eqn
left ( {a sub 1 , a sub 2 , a sub 3} right )