I have the same problem when I want to split CSV files into its columns. The point I got is that I couldn't do it with a regexp, so I did it the way it would be done without regexps...

Basically, I read character by character and push the contexts I enter... For instance.... 

"This is a column","Yes, I know",12323,23123.23,"This is a \"column\""

[download]

should be splitted in 

This is a column
Yes, I know
12323
23123.23
This is a "column"

[download]

ok, no more talking... the code talks by itself... 

#!/usr/bin/perl -w

use strict;

my $origin = '"This is a column","Yes, I know",123123,23123.23,"This i
+s a \"column\""';
my @cols = parse_line($origin);
print join("\n", @cols)."\n";

sub parse_line {
    my $line = shift;
    my @contexts;
    my $context = "";
    my $column;
    my @cols;
    my $string_delim = '"';
    my $escape_char = "\\";
    my $field_delim = ',';
    for (my $i = 0; $i < length $line; $i++) {
        my $c = substr($line, $i, 1);
        if ($c eq $string_delim) {
            if ($context eq "string") {
                $context = shift @contexts;
            } elsif ($context eq "escape") {
                $column .= $c;
                $context = shift @contexts;
            } else {
                push @contexts, $context;
                $context = "string";
            }
        } elsif ($c eq $escape_char) {
            if ($context eq "escape") {
                $column .= $c;
                $context = shift @contexts;
            } else {
                push @contexts, $context;
                $context = "escape";
            }
        } elsif ($c eq $field_delim) {
            if ($context eq "string") {
                $column .= $c;
            } elsif ($context eq "escape") {
                $column .= $c;
                $context = shift @contexts;
            } else {
                push @cols, $column;
                undef $column;
            }
        } else {
            $column .= $c;
        }

        if ($i == length($line) - 1) {
            push @cols, $column;
            undef $column;
        }
    }
    return @cols;
}

[download]
daniel

In reply to Re: split $data, $unquoted_value; by ruoso
in thread split $data, $unquoted_value; by Ovid

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