I woul like to know why Perl thinks my call to walk within the subroutine is an indirect method call while the one at the bottom of the program is interpreted as a function call. 
Uncaught exception from user code:
    Can't call method "walk" on unblessed reference at treewalk.pl lin
+e 28.
    main::walk('ARRAY(0x15b220)') called at treewalk.pl line 34

[download]

#!/bin/env perl

use strict;
use warnings;
use diagnostics;


my $tree = 
  [
   "Accomplishments in the past week" => 'accomplishments.txt',
   "Plans for the next week"          =>
   [
    General   => 'plans.txt',
    Vacations => 'vacations.txt',
    Classes   => 'classes.txt'
   ],
   "Outstanding issues"               => 'issues.txt'
  ];


sub walk {
  my $t = shift ;

  while (my ($key, $val) = splice @$t, 0, 2) {
    if (!ref($val)) {
      print "$key => $val\n";
    } else {
      walk $val; ##### PROBLEM LINE
    }
  }

}
 
walk $tree;

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Edit: 2001-03-03 by neshura

In reply to Why was indirect object syntax inferred here?o by princepawn

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