Beefy Boxes and Bandwidth Generously Provided by pair Networks
There's more than one way to do things
 
PerlMonks  

Re: CSV File Parsing

by Tux (Abbot)
on Feb 28, 2013 at 20:55 UTC ( #1021114=note: print w/replies, xml ) Need Help??


in reply to CSV File Parsing

  • Do not use parse (), use getline ()
  • Use a lexical file handle
  • Never use an else branch if the if branch ends the enclosing scope (exit, return, die, last, )
  • Use auto_diag
  • Use positive logic for validation
# Use auto_diag to see all parsing errors immediately my $csv = Text::CSV_XS->new ({ binary => 1, auto_diag => 1, allow_whit +espace => 1 }); open my $fh, "<", $file_to_parse or die "Could not open '$file' $!"; while (my $row = $csv->getline ($fh)) { # Check first and third field to be numeric only (and not empty) $row->[0] =~ m/^[0-9]+$/ && $row->[2] =~ m/^[0-9]+$/ or exit; # wrong format # THERE CANNOT BE AN ELSE AFTER AN EXIT ! }

update: your sample data contains spaces. You will have to deal with those, as the current tests will fail for leading and training spaces. Adding allow_whitespace option to the constructor will help you here.


Enjoy, Have FUN! H.Merijn

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://1021114]
help
Chatterbox?
[ambrus]: ad code examples.
[ambrus]: I'm not trying to recommend PHP, but I think it has way too bad a name because of its past.
[ambrus]: This is different from MS Word, which was already a good editor in the pre-unicode days (in word for windows versions 2 and 6, which ran on windows 3 but also on windows 95), only it wasn't trying to solve the task of writing maths papers back then.
[Discipulus]: ah ok, sounds reasonable; with no fear: Perl all life long
[ambrus]: Mind you, LaTeX is currently still useful for writing math paper or snippet content without styling in such a way that the
[ambrus]: formatting conventions of a journal or website can be quickly applied to it, and MS Office and LibreOffice has not quite solved this (although it's better for this than it used to be),
[ambrus]: which is sort of a drawback compared to the ages of typewritten manuscripts representing content only to which the typesetter applies formatting, but that process required much more manual labor.
[ambrus]: If you want to typeset a manuscript, you can still do much less work then in the manual typesetting ages and get good formatting.
[ambrus]: All with only cheap modern computers and software.
[ambrus]: Something you can have at home and your corner print shop, without a whole printing press's worth of equipment.

How do I use this? | Other CB clients
Other Users?
Others rifling through the Monastery: (10)
As of 2017-09-26 11:14 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    During the recent solar eclipse, I:









    Results (293 votes). Check out past polls.

    Notices?