Quoting from the excellent "Perl Cookbook" -

Comma-seperated input is a deceptive and complex format. It sounds simple but involves a fairly complex escaping systembecause the fields themselves can contain commas. This makes pattern matching a solution complex and rules out the simple split /,/ .

This sums up the situation pretty well. There is no definition of a CSV format and something that works with one data format may not work with another. The book goes on to provide the following example code which I have modified to trim whitespace. This should work with Excel generated CSV files. 

#! /usr/bin/perl
#
use strict;

while (<DATA>)
{
    chomp; # avoid matching against newline
    my $words = join "=>", parse_csv($_);
    print "$words\n";
}

sub parse_csv
{
    my $text = shift;      # record containing comma-separated values
    my @new = ( );
    
    push @new, $+ while $text =~ m{
        \s*"([^\"\\]*(?:\\.[^\"\\]*)*)"\s*,?    # Matches a phrase tha
+t may contain commas
        | \s*([^,]+)\s*,?    # Something that is not a comma
        | \s*,    # Just a comma - no data
        }gx;

    push (@new, undef) if substr($text, -1,1)eq ',';
    return @new;
}

__DATA__
1,the,simple,case
"with","quoted" , "strings that contain spaces"
"with","quoted" , "comma, internally"
"with","quoted" , "comma, internally, with null data",,,

[download]

inman

In reply to Re: regular expression (search and destroy) by inman
in thread regular expression (search and destroy) by data67

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