in reply to Re: Re: Re: Any Point in Uploading Tie::SortedHash
in thread Any Point in Uploading Tie::SortedHash

This looks potentially really cool and I would like to incorporate this technique as one of the possible options of my module. The problem is I can't seem to get DB_BTREE->{compare} to do anything meaningful. I get the same result no matter what I make the sort routine.
#!/usr/bin/perl -w use strict; use DB_File; tie my %h, 'DB_File', undef, O_RDWR|O_CREAT, 0666, $DB_BTREE or die "DB_File tie failed: $!"; #$DB_BTREE->{compare} = sub { $h{$_[1]} <=> $h{$_[0]} }; #$DB_BTREE->{compare} = sub { $h{$_[0]} <=> $h{$_[1]} }; #$DB_BTREE->{compare} = sub { $_[0] cmp $_[1] }; #$DB_BTREE->{compare} = sub { $_[1] cmp $_[0] }; %h = ( 'John' => 33, 'Jacob' => 29, 'Jingle' => 15, 'Heimer' => 48, 'Smitz' => 12, ); print "$_ : $h{$_}\n" for keys %h;

What am I missing? - L~R

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Re: Re: Re: Re: Re: Any Point in Uploading Tie::SortedHash
by danger (Priest) on Sep 06, 2003 at 18:41 UTC

    Set $DB_BTREE->{compare} before tieing the hash. However, accessing the tied hash in the compare routine leads to deep recursion (FETCH method uses the compare routine to navigate the tree).

      While this sounded like a good thing, it doesn't provide near enough functionality for the purpose of my module.
    • Ability to change the sort routine on the fly
    • Ability to sort on anything to include values

      Thanks anyway - I learned something new which is always a good thing

      Cheers - L~R