Hi all, I've written a small module that I would like to contribute to CPAN. It's a very simple, generic data structure, resembling a FIFO with time-delay. Since this is a totally generic data structure, I thought the "top-level" name of 'DelayLine' might not be totally stupid. I've also contemplated putting it in the 'Data::' namespace, but modules here are not general data structures, but concern data conversion. I'm not entirely happy about using a top-level name, but maybe this is the most suitable place after all? I've tried to solicit comments on this matter on c.l.p.modules without any luck, so your comments are more than welcome. So until something more appropriate comes up, the suggested module listing is as follows: Name DSLI Description Info ----------- ---- ---------------------------------- -------- DelayLine bdpO Simple time-delay data structure LTHEGLER The module is available from http://www.thegler.dk/perl/modules/DelayLine-0.01.tar.gz but I've included the documentation below for your convenience. Kind regards, Lars Thegler [EMAIL PROTECTED] -- NAME DelayLine - Simple time-delay data stucture SYNOPSIS use DelayLine; my $dl = DelayLine->new(delay => $defaultdelay); $dl->in($item); [...] if (my $ob = $dl->out()) { # do stuff with $ob } DESCRIPTION The `DelayLine' is a simple two-port data structure, like a FIFO, but with variable delay. Each object put into the input of the DelayLine will appear on the output only after some pre-determined amount of time has elapsed. This time can be set as a default for the DelayLine, or can be individually overridden for each object put into the DelayLine. If the default delay time is set to zero, and is not overridden for the individual objects, the DelayLine mimics a straightforward FIFO. The DelayLine accepts any scalar value as input, including references. The DelayLine is a very useful component when building simple event loops. Methods `DelayLine' provides the following methods: DelayLine->new( [ delay => DELAY [, debug => DEBUG ]] ) Returns a newly created `DelayLine' object. The default delay is 0 seconds, unless an optional `DELAY' time in seconds is given. Debugging is turned off by default. Setting DEBUG to true, enables debugging output to STDOUT. The parameter naming style is very flexible: the keyword can be in lower, upper or mixed case, and can be optionally prefixed with a dash. Thus, the following are all equivalent: $dl = DelayLine->new( -delay => 42 ); $dl = DelayLine->new( delay => 42 ); $dl = DelayLine->new( -Delay => 42 ); $dl = DelayLine->new( DELAY => 42 ); $dl = DelayLine->new( -deLaY => 42 ); `new()' can be called as a class (static) or object method. Calling `new()' as an object method is only a convenience; no data from the original DelayLine is carried over into the newly created object. $DL->in( OBJ [, DELAY ] ) This method puts object `OBJ' into DelayLine `$DL'. The object `OBJ' can be any scalar value, including references. The default delay as set in the `new()' method is used, unless overridden by setting `DELAY'. $DL->out() This method fetches objects from the out from the DelayLine `$DL'. Returns the first of the timed-out objects, if any. Returns `undef' if the DelayLine is empty, of if no objects in the DelayLine have timed out yet. $DL->delay( [ DELAY ] ) Returns the current default delay setting of the DelayLine. If the optional value DELAY is set, sets a new default delay value. $DL->debug( [ DEBUG ] ) Returns the current debug setting of the DelayLine. If the optional value DEBUG is set, sets a new debug value. If the debug value is set (true), calling any of the 'active' methods (`in()' or `out()' will yield a short debug message on STDERR. BUGS This is a fairly simple module, so no serious bugs are expected. Patches are welcome, though. COPYRIGHT Copyright (c) 2000 Lars Thegler. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. AUTHOR Lars Thegler <[EMAIL PROTECTED]>
