#!/usr/bin/perl
use 5.014;

#994367

my @data = ( 'R00005: 00330: C01010 => C00011', 
             'R00005: 00791: C01010 => C00011', 
             'R00005: 01100: C01010 <=> C00011',  
             'R00006: 00770: C00022 => C00900', 
             'R00008: 00362: C06033 => C00022', 
             'R00008: 00660: C00022 => C06033',  
             'R00010: 00500: C01083 => C00031',  
             'R00013: 00630: C00048 => C01146',  
             'R00013: 01100: C00048 <=> C01146', 
            );

for my $data (@data) {
    if ( $data =~ /(R\d{5}).+)/ ) {   # Match on and capture any line which 
                                      # contains the sequence R, 5 digits, and
                                      # something more
                                      # The parens in the regex capture the
                                      # match to $1 (but are not used here)
                                      # which could be used in other applications.


        say "\t Match on data $data. Hooray!";
    } else {
        say "No match on data $data";
    }
}

# do it again for those beginning "R00005" ONLY
say "\n\n doing it again for 'R00005' ONLY";
for my $data (@data) {
    if ( $data =~ /(R0{4})(5)(.+)/ ) {
        say "\t Match on data " . $1 . $2 . $3 . " Hooray!";  # 3 captures, 
                                                              # print'em
                                                       # NOT a good practice;
                                                       # illustrate ONLY one aspect
                                                       # of regex captures 

    } else {
        say "No match on data $data";
    }
}

=head output:

         Match on data R00005: 00330: C01010 => C00011. Hooray!
         Match on data R00005: 00791: C01010 => C00011. Hooray!
         Match on data R00005: 01100: C01010 <=> C00011. Hooray!
         Match on data R00006: 00770: C00022 => C00900. Hooray!
         Match on data R00008: 00362: C06033 => C00022. Hooray!
         Match on data R00008: 00660: C00022 => C06033. Hooray!
         Match on data R00010: 00500: C01083 => C00031. Hooray!
         Match on data R00013: 00630: C00048 => C01146. Hooray!
         Match on data R00013: 01100: C00048 <=> C01146. Hooray!


 doing it again for 'R00005' ONLY
         Match on data R00005: 00330: C01010 => C00011. Hooray!
         Match on data R00005: 00791: C01010 => C00011. Hooray!
         Match on data R00005: 01100: C01010 <=> C00011. Hooray!
No match on data R00006: 00770: C00022 => C00900
No match on data R00008: 00362: C06033 => C00022
No match on data R00008: 00660: C00022 => C06033
No match on data R00010: 00500: C01083 => C00031
No match on data R00013: 00630: C00048 => C01146
No match on data R00013: 01100: C00048 <=> C01146

=cut