...?[](...$[] = [ USER_ENTITY_NAME ], text${} = { this is a test })...

MATCH = [ USER_ENTITY_NAME ]
MATCH = { this is a test }
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a[] = [ this is a [ test ] { test2 } ]

MATCH = [ this is a [ test ] { test2 } ]
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a{} = { this is a { test } [ test2 ] }

MATCH = { this is a { test } [ test2 ] }
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{ a { b [ {}c{} ] d } e } = [ f [ g { []h[] } i ] j ]

MATCH = { a { b [ {}c{} ] d } e }
MATCH = [ f [ g { []h[] } i ] j ]
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{}[]{ {}[] }[]{} - []{}[ []{} ]{}[]

MATCH = { {}[] }
MATCH = [ []{} ]
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