You could get the results desired, if you delay their evaluation, and use slightly strange-looking syntax : 
my %h; 
%hash = ( 1 => { ONE       => 'testdir',
                 TWO       => 'tmpdir' },
          2 => { LOCATIONA => sub{ qq($hash{1}{ONE}/$hash{1}{TWO}/my_f
+ile.txt)},   # Note - wrapped in "sub"
                 LOCATIONB => sub{qq($hash{1}{TWO}/$hash{1}{ONE}/my_fi
+le.txt)} } 
);

print $hash{2}{LOCATIONA}(),qq( = location a\n); 
#When called like a sub call, produces:
#   testdir/tmpdir/my_file.txt = location a

[download]
For complete consistency, you would probably wrap the values corresponding to ONE and TWO in sub's as well.

     "Income tax returns are the most imaginative fiction being written today." -- Herman Wouk

In reply to Re: Can a hash self reference? by NetWallah
in thread Can a hash self reference? by tcf03

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