> If I feed it 'jones-123’ it dies with ‘jones, - , 123’ as I expected. But if I feed it ‘jones-‘ omitting the number on the end, it dies with no matches at all (or blanks): ‘ , , ‘ and I cannot figure out why it does not die with ‘jones, -, ' and would appreciate an explanation. Many thanks!
$student_id = lc $student_info_hash{student_id}; # Impose lower case $student_id =~ s/\s//xmsg; # Remove whitespace $student_id =~ m{ \A([a-z]+) # match and capture leading alphabetics (-) # hyphen to separate surname from student number ([0-9]+\z) # match and capture trailing digits }xms; # Perl Best Practices $student_surname = $1; my $hyphen = $2; $student_number = $3; die "$student_surname, $hyphen, $student_number”; ([0-9]+\z) means "capture one or more digits (same as "\d+") at the end of the string/before a newline - so m{ \A([a-z]+) # match and capture leading alphabetics (-) # hyphen to separate surname from student number ([0-9]*)\z # match and capture trailing digits }xms; # Perl Best Practices zero or more digits On Fri, Jun 1, 2018 at 3:54 PM, Rick T <p...@reason.net> wrote: > This is a newbie question, I’m sure. But I get perplexed easily! > > The follow code segment expects to receive a $student_id consisting of a > surname followed by a hyphen followed by a number. The die is for testing > what I’m doing. > > If I feed it 'jones-123’ it dies with ‘jones, - , 123’ as I expected. But > if I feed it ‘jones-‘ omitting the number on the end, it dies with no > matches at all (or blanks): ‘ , , ‘ and I cannot figure out why it does not > die with ‘jones, -, ' and would appreciate an explanation. Many thanks! > > $student_id = lc $student_info_hash{student_id}; # Impose lower case > $student_id =~ s/\s//xmsg; # Remove whitespace > > $student_id =~ > m{ > \A([a-z]+) # match and capture leading alphabetics > (-) # hyphen to separate surname from student number > ([0-9]+\z) # match and capture trailing digits > }xms; # Perl Best Practices > $student_surname = $1; > my $hyphen = $2; > $student_number = $3; > die "$student_surname, $hyphen, $student_number”; > > Rick Triplett > > -- a Andy Bach, afb...@gmail.com 608 658-1890 cell 608 261-5738 wk