NAME

       Mail::IMAPClient::MessageSet - ranges of message sequence numbers

SYNOPSIS

        my @msgs = $imap->search("SUBJECT","Virus"); # returns 1,3,4,5,6,9,10
        my $msgset = Mail::IMAPClient::MessageSet->new(@msgs);
        print $msgset;  # prints "1,3:6,9:10"

        # add message 14 to the set:
        $msgset += 14;
        print $msgset;  # prints "1,3:6,9:10,14"

        # add messages 16,17,18,19, and 20 to the set:
        $msgset .= "16,17,18:20";
        print $msgset;  # prints "1,3:6,9:10,14,16:20"

        # Hey, I didn't really want message 17 in there; let's take it out:
        $msgset -= 17;
        print $msgset;  # prints "1,3:6,9:10,14,16,18:20"

        # Now let's iterate over each message:
        for my $msg (@$msgset)
        {  print "$msg\n";  # Prints: "1\n3\n4\n5\n6..16\n18\n19\n20\n"
        }
        print join("\n", @$msgset)."\n";     # same simpler
        local $" = "\n"; print "@$msgset\n"; # even more simple

DESCRIPTION

       The Mail::IMAPClient::MessageSet module is designed to make life easier for programmers who need to
       manipulate potentially large sets of IMAP message UID's or sequence numbers.

       This module presents an object-oriented interface into handling your message sets. The object reference
       returned by the new method is an overloaded reference to a scalar variable that contains the message
       set's compact RFC2060 representation. The object is overloaded so that using it like a string returns
       this compact message set representation. You can also add messages to the set (using either a '.='
       operator or a '+=' operator) or remove messages (with the '-=' operator). And if you use it as an array
       reference, it will humor you and act like one by calling unfold for you.

       RFC2060 specifies that multiple messages can be provided to certain IMAP commands by separating them with
       commas. For example, "1,2,3,4,5" would specify messages 1, 2, 3, 4, and (you guessed it!) 5. However, if
       you are performing an operation on lots of messages, this string can get quite long.  So long that it may
       slow down your transaction, and perhaps even cause the server to reject it. So RFC2060 also permits you
       to specify a range of messages, so that messages 1, 2, 3, 4 and 5 can also be specified as "1:5".

       This is where Mail::IMAPClient::MessageSet comes in. It will convert your message set into the shortest
       correct syntax. This could potentially save you tons of network I/O, as in the case where you want to
       fetch the flags for all messages in a 10000 message folder, where the messages are all numbered
       sequentially. Delimited as commas, and making the best-case assumption that the first message is message
       "1", it would take 48893 bytes to specify the whole message set using the comma-delimited method. To
       specify it as a range, it takes just seven bytes (1:10000).

       Note that the Mail::IMAPClient Range method can be used as a short-cut to specifying
       "Mail::IMAPClient::MessageSet->new(@etc)".)

CLASS METHODS

       The only class method you need to worry about is new. And if you create your Mail::IMAPClient::MessageSet
       objects via Mail::IMAPClient's Range method then you don't even need to worry about new.

   new
       Example:

        my $msgset = Mail::IMAPClient::MessageSet->new(@msgs);

       The new method requires at least one argument. That argument can be either a message, a comma-separated
       list of messages, a colon-separated range of messages, or a combination of comma-separated messages and
       colon-separated ranges. It can also be a reference to an array of messages, comma-separated message
       lists, and colon separated ranges.

       If more then one argument is supplied to new, then those arguments should be more message numbers, lists,
       and ranges (or references to arrays of them) just as in the first argument.

       The message numbers passed to new can really be any kind of number at all but to be useful in a
       Mail::IMAPClient session they should be either message UID's (if your Uid parameter is true) or message
       sequence numbers.

       The new method will return a reference to a Mail::IMAPClient::MessageSet object. That object, when double
       quoted, will act just like a string whose value is the message set expressed in the shortest possible
       way, with the message numbers sorted in ascending order and with duplicates removed.

OBJECT METHODS

       The only object method currently available to a Mail::IMAPClient::MessageSet object is the unfold method.

   unfold
       Example:

           my $msgset = $imap->Range( $imap->messages ) ;
           my @all_messages = $msgset->unfold;

       The unfold method returns an array of messages that belong to the message set. If called in a scalar
       context it returns a reference to the array instead.

OVERRIDDEN OPERATIONS

       Mail::IMAPClient::MessageSet overrides a number of operators in order to make manipulating your message
       sets easier. The overridden operations are:

   stringify
       Attempts to stringify a Mail::IMAPClient::MessageSet object will result in the compact message
       specification being returned, which is almost certainly what you will want.

   Auto-increment
       Attempts to autoincrement a Mail::IMAPClient::MessageSet object will result in a message (or messages)
       being added to the object's message set.

       Example:

           $msgset += 34;
           # Message #34 is now in the message set

   Concatenate
       Attempts to concatenate to a Mail::IMAPClient::MessageSet object will result in a message (or messages)
       being added to the object's message set.

       Example:

           $msgset .= "34,35,36,40:45";
           # Messages 34,35,36,40,41,42,43,44,and 45 are now in the message set

       The ".=" operator and the "+=" operator can be used interchangeably, but as you can see by looking at the
       examples there are times when use of one has an aesthetic advantage over use of the other.

   Autodecrement
       Attempts to autodecrement a Mail::IMAPClient::MessageSet object will result in a message being removed
       from the object's message set.

       Examples:

           $msgset -= 34;
           # Message #34 is no longer in the message set
           $msgset -= "1:10";
           # Messages 1 through 10 are no longer in the message set

       If you attempt to remove a message that was not in the original message set then your resulting message
       set will be the same as the original, only more expensive. However, if you attempt to remove several
       messages from the message set and some of those messages were in the message set and some were not, the
       additional overhead of checking for the messages that were not there is negligible. In either case you
       get back the message set you want regardless of whether it was already like that or not.

AUTHOR

        David J. Kernen
        The Kernen Consulting Group, Inc

COPYRIGHT

        Copyright 1999, 2000, 2001, 2002 The Kernen Group, Inc.
        All rights reserved.

       This program is free software; you can redistribute it and/or modify it under the terms of either:

       a) the "Artistic License" which comes with this Kit, or
       b) the GNU General Public License as published by the Free Software Foundation; either version 1, or (at
       your option) any later version.

       This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
       the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See either the GNU General
       Public License or the Artistic License for more details. All your base are belong to us.