Better way to write this regex to match multi-ordered property list?
- by Andrew Philips
I've been whacking on this regex for a while, trying to build something that can pick out multiple ordered property values (DTSTART, DTEND, SUMMARY) from an .ics file. I have other options (like reading one line at a time and scanning), but wanted to build a single regex that can handle the whole thing.
SAMPLE PERL
# There has got to be a better way...
my $x1 = '(?:^DTSTART[^\:]*:(?<dts>.*?)$)';
my $x2 = '(?:^DTEND[^\:]*:(?<dte>.*?)$)';
my $x3 = '(?:^SUMMARY[^\:]*:(?<dtn>.*?)$)';
my $fmt = "$x1.*$x2.*$x3|$x1.*$x3.*$x2|$x2.*$x1.*$x3|$x2.*$x3.*$x1|$x3.*$x1.*$x2|$x3.*$x2.*$x1";
if ($evts[1] =~ /$fmt/smo) {
printf "lines:\n==>\n%s\n==>\n%s\n==>\n%s\n", $+{dts}, $+{dte}, $+{dtn};
} else {
print "Failed.\n";
}
SAMPLE DATA
BEGIN:VEVENT
UID:0A5ECBC3-CAFB-4CCE-91E3-247DF6C6652A
TRANSP:OPAQUE
SUMMARY:Gandalf_flinger1
DTEND:20071127T170005
DTSTART,lang=en_us:20071127T103000
DTSTAMP:20100325T003424Z
X-APPLE-EWS-BUSYSTATUS:BUSY
SEQUENCE:0
END:VEVENT
SAMPLE OUTPUT
lines:
==
20071127T103000
==
20071127T170005
==
Gandalf_flinger1
