And you could shorten that to just /::?|\s+/

Maybe I did not explain what I meant properly. I don't want to match ':' OR '::' OR ..., I want to match ':' THEN '::' THEN... I want to effectively change what the split operator uses as the splitting pattern mid-split. After the first field is found using the first delimeter pattern, it is discarded and the next field can only be delimited with the next pattern. The patterns move from left to right and MUST match in the order that they are presented in.

tigervamp

That is no a split then, that is a pattern match. The problem remains that a line like 'a::b:: c' will match according to your rules but the result will be 'a', ':b', 'c'. You can do this easily with recursion:

my @split_bits = qw( : :: \s+ );

my @result = wierd_split( 'foo:bar::baz  boo:foo::bar::baz', \@split_b
+its );
print "Got $_\n" for @result;

sub wierd_split {
    my ( $str, $to_do, $got ) = @_;
  return (@$got, $str) unless @$to_do;
    my $next_split = shift @$to_do;
    print scalar @$to_do, " splitting '$str' on '$next_split'", "\n";
    my ( $want, $next ) = $str =~ m/(.*?)$next_split(.*)/m;
    print "'$want' '$next'\n";
    push @{$got}, $want;
    # and now for a little recursion
    wierd_split( $next, $to_do, $got ) if $want;
}
__DATA__
2 splitting 'foo:bar::baz  boo:foo::bar::baz' on ':'
'foo' 'bar::baz  boo:foo::bar::baz'
1 splitting 'bar::baz  boo:foo::bar::baz' on '::'
'bar' 'baz  boo:foo::bar::baz'
0 splitting 'baz  boo:foo::bar::baz' on '\s+'
'baz' 'boo:foo::bar::baz'
Got foo
Got bar
Got baz
Got boo:foo::bar::baz
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tachyon

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