the input looks like

<man> ::= <blah>
<man> ::= <blah2>
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Ah, in that case you'll want to go with either davido's solution or pg's (whichever one you understand better). I wasn't sure from your original post whether that was the case.

$;=sub{$/};@;=map{my($a,$b)=($_,$;);$;=sub{$a.$b->()}}
split//,".rekcah lreP rehtona tsuJ";$\=$ ;->();print$/
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