On Tue, Mar 2, 2010 at 1:46 PM, John W. Krahn <jwkr...@shaw.ca> wrote:
> raphael() wrote: > >> >> Cool! I have to admit that is a "detailed" answer. >> Also thanks for clearing out the differences between these two.. >> >> ( my $ip = $last_page ) =~ m/([\d+\.]+)/; >> ( my $ip ) = ( $last_page ) =~ m/([\d+\.]+)/; >> >> Just to clear out any misunderstanding "by above one" >> I meant ( my $ip = $last_page ) =~ m/([\d+\.]+)/; >> Now am I getting this right that this is the *wrong syntax* to get list >> context. >> > > Correct, there is no list context in that statement. The parentheses are > required because the =~ operator has higher precedence than the = operator. > > > > Your post was very helpful since I didn't know about parenthesis (or lack >> of >> it) to capture values. >> >> I always did use parenthesis to capture values like >> ( my $ip ) = $last_page =~ m/*(*[\d+\.]+*)*/g; >> >> Now I *know* this works >> ( my $ip ) = $last_page =~ m/[\d+\.]+/g; >> > > Again, the '+' character is not a valid IP address character so it should > be removed from the character class and the '.' period character does not > need to be escaped inside a character class. > > The capturing parentheses are *required* when you only want to return > *part* of a pattern: > > ( my $ip ) = $last_page =~ /IP: *([\d.]+)/g; > > Or when you want to match a single pattern without the /g option: > > ( my $ip ) = $last_page =~ /([\d.]+)/; > > > > > > John > -- > The programmer is fighting against the two most > destructive forces in the universe: entropy and > human stupidity. -- Damian Conway > > -- > To unsubscribe, e-mail: beginners-unsubscr...@perl.org > For additional commands, e-mail: beginners-h...@perl.org > http://learn.perl.org/ > > > Yup. Got it. ( my $ip ) = $last_page =~ m/[\d.]+/g * parenthesis only if part of capture is required or without /g. * + not inside character class since we don't have ip like 192+. (silly me). * dot need not be escaped inside character class since it is no longer the king (meta character) ? * John is a helpful guy.
