[perl #123380] [BUG] A script that gives different results when executed from a file and when pasted into REPL

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# New Ticket Created by  Jirka Daněk 
# Please include the string:  [perl #123380]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=123380 >


$ ./perl6-m --version
This is perl6 version 2014.09 built on MoarVM version 2014.09

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$ ./perl6-m
> say 'a'.subst(/(.)/,{$0~$0});
aa
> say "%20" ~~ /:i \%(<[0..9A..F]>**2)/;
｢%20｣
 0 => ｢20｣

> say 'a'.subst(/(.)/,{$0~$0});
2020

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$ cat strangeregexp.pl
say 'a'.subst(/(.)/,{$0~$0});               # aa

say "%20" ~~ /:i \%(<[0..9A..F]>**2)/;      # ｢%20｣
                                            #   0 => ｢20｣

say 'a'.subst(/(.)/,{$0~$0});

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./perl6-m strangeregexp.pl
aa
｢%20｣
 0 => ｢20｣

aa

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