pattern matching through a whole document

r_mehmed has asked for the wisdom of the Perl Monks concerning the following question:

Monks! a.newbie

i'm working on a small web site where a text input should be pattern matched and all date formats such as(dd/mm/yyyy | dd-mm-yyyy) should converted into say :'01st January 2003'. I managed to do that(with the help of the Monastery) using memory parenthesis($1,$2 etc). The problem is i can apply it to the code only once,thus it matches and converts only the first match... this is the code:

#!perl 

use CGI;

$query = new CGI;
$source = $query->param('input');
print $query->header,
    $query->start_html('10222161'),
    $query->h1({-align=>center},'CAD Assignment 1B'),
    $query->p({-align=>center},'The corrected text is: '),
    $query->hr; 
        

$source =~ m!(\d{1,2})(\/|\-)(\d{1,2})(\/|\-)(\d{2,4})!g;

my $day = $1;
my $month = $3;
my $year = $5;

if($day == 1 or $day == 21 or day == 31){
    $day .='st';
    } elsif ($day == 2 or $day == 22){
    $day .='nd';
    } elsif ($day == 3 or $day == 23){
    $day .= 'rd';
    } else {
    $day .= 'th';
    }

if($month == 01){
    $month = 'January';
    } elsif ($month == 2){
    $month = 'February';
    } elsif ($month == 3){
    $month = 'March';
    } elsif ($month == 4){
    $month = 'April';
    } elsif ($month == 5){
    $month = 'May';
    } elsif ($month == 6){
    $month = 'June';
    } elsif ($month == 7){
    $month = 'July';
    } elsif ($month == 8){
    $month = 'August';
    } elsif ($month == 9){
    $month = 'September';
    } elsif ($month == 10){
    $month = 'October';
    } elsif ($month == 11){
    $month = 'November';
    } else {
    $month = 'December';
    }
print    $query->p({-align=>center},"$day $month $year"),
          $query->hr,
        $query->i({-align=>center},'10222161'),
        $query->end_html;
[download]

Many thanks in advance!

Comment on pattern matching through a whole document Download Code

Replies are listed 'Best First'.
Re: pattern matching through a whole document by BrowserUk (Patriarch) on Nov 01, 2002 at 13:51 UTC
One way to do this is to use the substitution operator s/// (see perlfunc and perlop) and use the e modifier to executed a small 'program' in the second part of the operator. By using arrays to store your months and day endings, you greatly simplify the logic of the code. `#!perl use strict; my @months = qw( -- January February March April May June July August +September October November December); my @dayends = qw( -- st nd rd th th th th th th th th th th th th th t +h th th th st nd rd th th th th th th th st); while(my $date = <DATA>) { chomp $date; $date =~ s!(\d{1,2})(\/\|\-)(\d{1,2})(\/\|\-)(\d{2,4})! $1 . $dayend +s[$1] . ' ' . $months[$3] . ' ' . $5 !eg; print $date, $/; } __DATA__ 3/3/2002 5/11/2002 31-07-2002 1-4-02 21-2-02 31-12-2002` [download] Gives output `c:\test>209700 3rd March 2002 5th November 2002 31st July 2002 1st April 02 21st February 02 31st December 2002 c:\test>` [download] Maybe you can adapt this to your purposes. Nah! Your thinking of Simon Templar, originally played by Roger Moore and later by Ian Ogilvy	[reply] [d/l] [select]
Re: Re: pattern matching through a whole document by r_mehmed (Sexton) on Nov 01, 2002 at 15:18 UTC
many thanks, your code has been of great help!i know all this isn't thah hard to do,but it takes time. will do my best not to ask stupd Q all the time... r_mehmed stupid:gravity	[reply]
Re: pattern matching through a whole document by Thelonius (Priest) on Nov 01, 2002 at 13:49 UTC
$query->h1({-align=>center},'CAD Assignment 1B'), Homework! By the way, you should read the chapter on arrays. `@months = qw(January February March ...);` [download]	[reply] [d/l]
Re: pattern matching through a whole document by dingus (Friar) on Nov 01, 2002 at 13:52 UTC
put the regex and processing in a while loop. I.e. `while($source =~ m!(\d{1,2})(\/\|\-)(\d{1,2})(\/\|\-)(\d{2,4})!g) { my $day = $1; my $month = $3; my $year = $5; # process stuff print $query->p({-align=>center},"$day $month $year"), }` [download] Note: 1 unless you know there are no confusing spaces in your dates you may wish to have the middle expressions as \s(\/\|\-)\s 2 if you use the (?: ) syntax you will not $2 and $4 defined. Then you can do while(($day,$month,$year) =(source=~ /.../g) ) { and assign the values as you test the RE. Combining my notes would give you a while line `while(($day,$month,$year) = ($source =~ m!(\d{1,2})\s(?:\/\|\-)(\d{1,2})\s\s(?:\s(?:\/\|\-)\s* +(\d{2,4})!g) ){` [download] which may or may not be easier to understand.	[reply] [d/l] [select]