Re: Limiting String Length
There is a length() function.
eg. $string = 'my little little string';
$lengthOfstring = length($string);
if ( $lengthOfstring >= 4096 blah) {
blah
}
- Original Message -
From: "Chuck Ivy" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, June 21, 2001 2:31 PM
Subject: Limiting String Length
> I've got a simple message board script that I cobbled together. It seems
> to have been the target of some abuse, though.
>
> The latest patch I'd like to apply to the code would be limiting the
> length of a message posted to, say, 4096 characters.
>
> Now, looking up the substring function, it looks like if the original
> string were less than the size of my substring, it would pad my variable
> until it was 4096 characters.
>
> Would a regex be better? Matching for up to 4096 characters and
> replacing the string with $1?
>
> I recall some programming languages treat strings as arrays of
> characters. Is there a quick perl function or variable that represents
> the length of a string? I didn't see any obvious entries in the index of
> Programming Perl, but I may have been looking in the wrong place.
>
> Or is this a good place for formatting commands?
>
> Any suggestions welcome.
_
Do You Yahoo!?
Get your free @yahoo.com address at http://mail.yahoo.com
Re: Limiting String Length
hahah, sure, why dont we do this then:
my $coolstring;
my @foo = split '', $str;
for (0..4095) { $coolstring .= $foo[$_] }
or how about this one:
my $foo = reverse $str;
while (length $foo > 4096) { $foo =~ s/.(.+)/$1/seg; }
$str = reverse $foo;
and no, i wont be held accountable for any loss of performance in your
script =)
TMTOWTDI ;-)
Jos
> @str = $str =~ /(.)/;
> $#str = 4095;
> $str = join '', @str;
>
> Hey, TMTOWTDI, though you shouldn't overDO it =o)
>
Re: [OT] Limiting String Length
--- Jeff 'japhy' Pinyan <[EMAIL PROTECTED]> wrote: > On Jun 21, Paul said: > > >--- Chuck Ivy <[EMAIL PROTECTED]> wrote: > >> I recall some programming languages treat strings as arrays of > >> characters. Is there a quick perl function or variable that > >> represents > >> the length of a string? I didn't see any obvious entries in the > index > >> of > >> Programming Perl, but I may have been looking in the wrong place. > > > >I'd agree with Japhy's substring suggestion, but I think you could > do > >something like this if you just wanted to play array games with the > >string: > > > > @str = $str =~ /(.)/; > > $#str = 4095; > > $str = join '', @str; > > Ewww. ;) First, you need the /s modifier on the regex. Second, you > need > the /g modifier on the regex. Third, you don't need the () in the > regex. > > @chars = $str =~ /./gs; > > Fourth, split() is far nicer to look at. > > @chars = split //, $str; > > Fifth, just join() the elements you want. > > $str = join '', @chars[0 .. 4095]; > > Sixth, get rid of the array. > > $str = join '', (split //, $str)[0 .. 4095]; > > But we're not using this approach anyway, are we? ;) LOL -- what he said. =o) __ Do You Yahoo!? Get personalized email addresses from Yahoo! Mail http://personal.mail.yahoo.com/
Re: Limiting String Length
On Jun 21, Paul said: >--- Chuck Ivy <[EMAIL PROTECTED]> wrote: >> I recall some programming languages treat strings as arrays of >> characters. Is there a quick perl function or variable that >> represents >> the length of a string? I didn't see any obvious entries in the index >> of >> Programming Perl, but I may have been looking in the wrong place. > >I'd agree with Japhy's substring suggestion, but I think you could do >something like this if you just wanted to play array games with the >string: > > @str = $str =~ /(.)/; > $#str = 4095; > $str = join '', @str; Ewww. ;) First, you need the /s modifier on the regex. Second, you need the /g modifier on the regex. Third, you don't need the () in the regex. @chars = $str =~ /./gs; Fourth, split() is far nicer to look at. @chars = split //, $str; Fifth, just join() the elements you want. $str = join '', @chars[0 .. 4095]; Sixth, get rid of the array. $str = join '', (split //, $str)[0 .. 4095]; But we're not using this approach anyway, are we? ;) -- Jeff "japhy" Pinyan [EMAIL PROTECTED] http://www.pobox.com/~japhy/ I am Marillion, the wielder of Ringril, known as Hesinaur, the Winter-Sun. Are you a Monk? http://www.perlmonks.com/ http://forums.perlguru.com/ Perl Programmer at RiskMetrics Group, Inc. http://www.riskmetrics.com/ Acacia Fraternity, Rensselaer Chapter. Brother #734 ** Manning Publications, Co, is publishing my Perl Regex book **
Re: Limiting String Length
On Thu, Jun 21, 2001 at 11:31:21AM -0700, Chuck Ivy wrote:
> Now, looking up the substring function, it looks like if the original
> string were less than the size of my substring, it would pad my variable
> until it was 4096 characters.
> perl -wle 'foreach my $str(qw(foo foobarblahdoo))
{ print "[", substr($str, 0, 10), "]" };'
[foo]
[foobarblah]
The beauty of Perl is that you can try things very easily. You should learn
to do this.
Michael
--
Administrator www.shoebox.net
Programmer, System Administrator www.gallanttech.com
--
Re: Limiting String Length
--- Chuck Ivy <[EMAIL PROTECTED]> wrote: > I've got a simple message board script that I cobbled together. It > seems to have been the target of some abuse, though. > > The latest patch I'd like to apply to the code would be limiting the > length of a message posted to, say, 4096 characters. > > Now, looking up the substring function, it looks like if the original > > string were less than the size of my substring, it would pad my > variable > until it was 4096 characters. > > Would a regex be better? Matching for up to 4096 characters and > replacing the string with $1? > > I recall some programming languages treat strings as arrays of > characters. Is there a quick perl function or variable that > represents > the length of a string? I didn't see any obvious entries in the index > of > Programming Perl, but I may have been looking in the wrong place. > > Or is this a good place for formatting commands? > > Any suggestions welcome. I'd agree with Japhy's substring suggestion, but I think you could do something like this if you just wanted to play array games with the string: @str = $str =~ /(.)/; $#str = 4095; $str = join '', @str; Hey, TMTOWTDI, though you shouldn't overDO it =o) __ Do You Yahoo!? Get personalized email addresses from Yahoo! Mail http://personal.mail.yahoo.com/
Re: Limiting String Length
On 21 Jun 2001 14:39:47 -0400, Chas Owens wrote: > How about > > use constant MAXSTRLENGTH => 4096; > > substr($string, MAXSTRLENGTH - 1, -1) = '' unless(length($strlen) < > MAXSTRLENGTH); > Oops, let me ammend that to use constant MAXSTRLENGTH => 4096; substr($str, MAXSTRLENGTH - 1) unless (length($str) < MAXSTRLENGTH); Sleep dep sucks. -- Today is Boomtime, the 26th day of Confusion in the YOLD 3167 Umlaut Zebra über alles!
Re: Limiting String Length
How about use constant MAXSTRLENGTH => 4096; substr($string, MAXSTRLENGTH - 1, -1) = '' unless(length($strlen) < MAXSTRLENGTH); On 21 Jun 2001 11:31:21 -0700, Chuck Ivy wrote: > I've got a simple message board script that I cobbled together. It seems > to have been the target of some abuse, though. > > The latest patch I'd like to apply to the code would be limiting the > length of a message posted to, say, 4096 characters. > > Now, looking up the substring function, it looks like if the original > string were less than the size of my substring, it would pad my variable > until it was 4096 characters. > > Would a regex be better? Matching for up to 4096 characters and > replacing the string with $1? > > I recall some programming languages treat strings as arrays of > characters. Is there a quick perl function or variable that represents > the length of a string? I didn't see any obvious entries in the index of > Programming Perl, but I may have been looking in the wrong place. > > Or is this a good place for formatting commands? > > Any suggestions welcome. > -- Today is Boomtime, the 26th day of Confusion in the YOLD 3167 Keep the Lasagna flying!
Re: Limiting String Length
On Jun 21, Chuck Ivy said: >Now, looking up the substring function, it looks like if the original >string were less than the size of my substring, it would pad my variable >until it was 4096 characters. > >Would a regex be better? Matching for up to 4096 characters and >replacing the string with $1? This is NOT the place to use a regex. Just use the substr() function to remove all characters after the 4096th. substr($entry, 4096) = "" if length($entry) > 4096; or $entry = substr($entry, 0, 4096); >I recall some programming languages treat strings as arrays of >characters. Is there a quick perl function or variable that represents >the length of a string? I didn't see any obvious entries in the index of >Programming Perl, but I may have been looking in the wrong place. Perl's strings can't be manipulated as arrays at the high-end level (that's not to say they're not implemented as char* in the source code). -- Jeff "japhy" Pinyan [EMAIL PROTECTED] http://www.pobox.com/~japhy/ I am Marillion, the wielder of Ringril, known as Hesinaur, the Winter-Sun. Are you a Monk? http://www.perlmonks.com/ http://forums.perlguru.com/ Perl Programmer at RiskMetrics Group, Inc. http://www.riskmetrics.com/ Acacia Fraternity, Rensselaer Chapter. Brother #734 ** Manning Publications, Co, is publishing my Perl Regex book **
