This simpler version 
$var = 'by_title';
# or $var = \&by_title;
sort $var @array;

[download]
will work, where $var can be given either the name of the subroutine or a reference to it. If validation of the sub name is necessary, it ought to be done separately from the call to sort.
We're not really tightening our belts, it just feels that way because we're getting fatter.

In reply to Re^2: Sort by what? by Roy Johnson
in thread Sort by what? by Anonymous Monk

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