Re^2: Regexp issue

assuming you just want to match a leading double-quote followed by something other than a double-quote

I forgot to mention that i have to parse CSV rows, so i have to match a leading double-quote followed by EXACTLY something other than a double-quote, because a third double-quote will be escaped by the previous one:

"18/02/2018" <- in this case the record is 18/02/2018

""18/02/2018" <- in this case the record is invalid

"""18/02/2018" <- in this case the record is "18/02/2018

Comment on Re^2: Regexp issue

Replies are listed 'Best First'.
Re^3: Regexp issue by hippo (Archbishop) on Feb 22, 2018 at 16:10 UTC
Previous advice from others about using a module notwithstanding, this additional requirement puts it well into "If it gets any fancier" territory. Here, therefore, is the test: `use strict; use warnings; use Test::More; my @good = ( '"18/02/2018"', '"""18/02/2018"' ); my @bad = ( '""18/02/2018"' ); my $re = qr/^"("")?[^"]/; plan tests => @good + @bad; for my $str (@good) { like ($str, $re, "$str matched"); } for my $str (@bad) { unlike ($str, $re, "$str not matched"); }` [download]	[reply] [d/l]

Replies are listed 'Best First'.

Re^3: Regexp issue
by hippo (Archbishop) on Feb 22, 2018 at 16:10 UTC

Previous advice from others about using a module notwithstanding, this additional requirement puts it well into "If it gets any fancier" territory. Here, therefore, is the test:

use strict;
use warnings;

use Test::More;

my @good = (
    '"18/02/2018"',
    '"""18/02/2018"'
);

my @bad = (
    '""18/02/2018"'
);

my $re = qr/^"("")?[^"]/;

plan tests => @good + @bad;

for my $str (@good) {
    like ($str, $re, "$str matched");
}
for my $str (@bad) {
    unlike ($str, $re, "$str not matched");
}
[download]

[reply]
[d/l]