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Package TWiki::ListIterator

Iterator over a list

On this page:

new(\@list)

Create a new iterator over the given list. Designed primarily for operations over fully defined lists of object references. The list is not damaged in any way.

hasNext() -> $boolean

Returns false when the iterator is exhausted.

my $it = new TWiki::ListIterator(\@list);
while ($it->hasNext()) {
   ...

next() -> $data

Return the next entry in the list.

The iterator object can be customised to pre- and post-process entries from the list before returning them. This is done by setting two fields in the iterator object:

For example,

my @list = ( 1, 2, 3 );

my $it = new TWiki::ListIterator(\@list);
$it->{filter} = sub { return $_[0] != 2 };
$it->{process} = sub { return $_[0] + 1 };
while ($it->hasNext()) {
    my $x = $it->next();
    print "$x, ";
}
will print
2, 4



Revision: r1 - 2008-01-22 - 11:21:26 - TWikiContributor

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