Mail::IMAPClient::MessUsereContributed Perl DocMail::IMAPClient::MessageSet(3)NAMEMail::IMAPClient::MessageSet - ranges of message sequence nummers
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 specifiy 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 OPERATIONSMail::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 negligable. 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.
perl v5.14.2 2010-10-04 Mail::IMAPClient::MessageSet(3)
