[perl #131701] [PARSER] Failure to parse `[[],]`

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# New Ticket Created by  Zoffix Znet 
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Works (space between brackets and <a>):

    $ perl6 -e 'dd [[ <a>],]'
    [["a"],]

Doesn't (no space):

    $ perl6 -e 'dd [[<a>],]'
    ===SORRY!=== Error while compiling -e
    Unable to parse expression in bracketed infix; couldn't find final ']' 
    at -e:1
    ------> dd [[<⏏a>],]