How to join lines in between 2 conditions - perl

Question

I'm listing a program to customly clean up a phonebook .vcf file.
I can't figure out how to place in a single string variable everything between start with /^NOTE.+:/ and end before /X-ACCOUNT.*:/. Please consider there were presence of \n I'd like preserve for future contact formatting:
ADR;WORK;X-SYNCMLREF507891:;;NUENSCfff STRASSE 3-5;RIESCHWEILER;;66509;Germania
ORG:aaaa & CO. KG
NOTE;ENCODING=QUOTED-PRINTABLE:Hall 30 F35=0A*ddddd#jggggine.com =0A014 =
EURO =0A*kkkk#ggggne.com =0A=
Bjjj#rrrLINE.COM
X-ACCOUNT:Local Phone Account;Phone
maybe using any foreach loop. but I can't concatenate only what I need and stop at the right point:
foreach $in (<IN>){
if($in =~ /^NOTE.*:|=$/){
unless($in =~ /^[A-Z]+:/){
$in =~ s/(.+=$)\n//;
$inn .= $1;
}
}
$a = $a;
}
Any recomandations ?

Answer 1

More or less this:
$inn .= $in if (($in =~ /^NOTE/ .. $in =~ /^X-ACCOUNT/) && $in !~ /^X-ACCOUNT/);
Using implicit $_ would make it shorter, perhaps:
while(<IN>) {
$inn .= $_ if (/^NOTE/ .. /^X-ACCOUNT/ and !/^X-ACCOUNT/);
See perlop for Range Operators and perhaps also perlop for why and is lower precedence than &&.

Answer 2

Less one-liney, perhaps more understandable : add a flag which indicates "currently accumulating lines in a variable"
$accumulating = 0;
foreach $in (<IN>){
if ($in =~ /^NOTE/) {
$accumulating = 1;
}
if ($in =~ /^X-ACCOUNT:/) {
$accumulating = 0;
# possibly : add some code which does something with $inn
}
if ($accumulating) {
$inn .= $in;
}
}