This can be solved much more generically in Perl 6 with mutator methods and topics: 
    print "$_\n" for map { .=subst(/er/, 'aler', :global) } @w;

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But what you're really asking for is something other than map here, I think...

In reply to Re^2: Perl oddities (s/// doesn't DWIM in map) by TimToady
in thread Perl oddities by brian_d_foy

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