You would dereference the scalar like this: 
sub sum {
    my ($term, $a, $next, $b) = @_;
    if ($a > $b) { return(0); }
    else { return( &$term($a) + &sum( &$term, (&$next($a)), (&$next($b
+)) ) ); }
}

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In reply to Re: Passing subroutines as arguments by @ncientgoose
in thread Passing subroutines as arguments by mvaline

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