Here is another interpration of the OP's requirements :
wanting to get an array ref containing ONLY the "title" element values, with the "_" substitution: 
my $Aref_new =[ map {(my $x=$_->{'title'}) 
                 =~ s/ /_/g;$x } @$AoH_orig]; 
print Dumper(\$Aref_new);

[download]
Note: Using the temporary "$x" allows the use of the "map" while preserving the original $AoH_orig, and getting the array ref (Hence the square brackets) containing the modified values.

     "Man cannot live by bread alone...
         He'd better have some goat cheese and wine to go with it!"

In reply to Re: Basic help with mapping by NetWallah
in thread Basic help with mapping by bradcathey

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