#!/usr/bin/perl

use strict;
use warnings;

my $index = 0;
my @nsi = (q~<nContractID>13523</nContractID>~);

my %xmlstring = (
    QueryCId => qr/<nC[o]?ntr[a]?ctID[^>]*>\s*(\d+)\s*<\/nC[o]?ntr[a]?ctID>/s,
);
my $cid;

my %xmlstring = (
    QueryCId => qr/<nC[o]?ntr[a]?ctID[^>]*>\s*(\d+)\s*<\/nC[o]?ntr[a]?ctID>/s,
);

print "\nreg: ", $nsi[$index] =~ /$xmlstring{'QueryCId'}/;

$nsi[$index] =~ /$xmlstring{'QueryCId'}/ ?
    print "\nMATCH" :
    print "\nNO MATCH";

$nsi[$index] =~ /$xmlstring{'QueryCId'}/ ?
    $cid = '' :
    $cid = 'I HATE YOU';

print "\nCID should be empty: ", $cid;

Summary of my perl5 (revision 5.0 version 8 subversion 3) configuration:
  Platform:
    osname=linux, osvers=2.6.5, archname=x86_64-linux-thread-multi
    uname='linux mahler 2.6.5 #1 smp thu aug 25 06:20:45 utc 2005 x86_64 x86_64 x86_64 gnulinux '
    config_args='-ds -e -Dprefix=/usr -Dvendorprefix=/usr -Dinstallusrbinperl -Dusethreads -Di_db -Di_dbm -Di_ndbm -Di_gdbm -Duseshrplib=true -Doptimize=-O2 -fmessage-length=0 -Wall -Wall -pipe'
    hint=recommended, useposix=true, d_sigaction=define
    usethreads=define use5005threads=undef useithreads=define usemultiplicity=define
    useperlio=define d_sfio=undef uselargefiles=define usesocks=undef
    use64bitint=define use64bitall=define uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS -fno-strict-aliasing -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
    optimize='-O2 -fmessage-length=0 -Wall -Wall -pipe',
    cppflags='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS -fno-strict-aliasing'
    ccversion='', gccversion='3.3.3 (SuSE Linux)', gccosandvers=''
    intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
    ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='cc', ldflags =' -L/usr/local/lib64'
    libpth=/lib64 /usr/lib64 /usr/local/lib64
    libs=-lm -ldl -lcrypt -lpthread
    perllibs=-lm -ldl -lcrypt -lpthread
    libc=/lib64//lib64/libc.so.6, so=so, useshrplib=true, libperl=libperl.so
    gnulibc_version='2.3.3'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-rdynamic -Wl,-rpath,/usr/lib/perl5/5.8.3/x86_64-linux-thread-multi/CORE'
    cccdlflags='-fPIC', lddlflags='-shared -L/usr/local/lib64'


Characteristics of this binary (from libperl): 
  Compile-time options: MULTIPLICITY USE_ITHREADS USE_64_BIT_INT USE_64_BIT_ALL USE_LARGE_FILES PERL_IMPLICIT_CONTEXT
  Locally applied patches:
        SPRINTF0 - fixes for sprintf formatting issues - CVE-2005-3962
  Built under linux
  Compiled at Dec 17 2005 03:22:14
  %ENV:
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