Btukfyl

I have several hundred PHP scripts that expect a language field to contain an ISO 639-1 2-character identifier. for example "en", which I now want to modify to support language codes qualified by country code, for example "fr-CA". In each of these scripts there is the following code:

    case 'lang':

    {       // language code

        if (strlen($value) == 2)

            $lang   = strtolower($value);

        break;

    }       // language code

which I want to modify to:

    case 'lang':

    {       // language code

        if (strlen($value) >= 2)

            $lang   = strtolower(substr($value,0,2));

        break;

    }       // language code

So I wrote a perl script to run over the entire directory tree and modify all of the matching scripts. For testing I have set the script up to create all of the modified scripts in a new directory structure:

use strict;

use warnings;

use 5.010;



use File::Find;

use File::Slurp;



my @content;

find( &wanted, '/home/jcobban/public_html/');



exit;



sub wanted {

    if (-f)

    {

        print "wanted: ",  $File::Find::name, "n";

        my $odir    = '/home/jcobban/testlang' . substr($File::Find::dir, 25);

        if ((substr $odir, -1) ne "/"){

            $odir   = "$odir/";

        }

        if (! -d $odir){

            mkdir $odir;

        }

        print "odir '$odir'n";

        my @lines   = read_file($File::Find::name);

        my $caselang    = 0;

        my $updated = 0;

        foreach my $line (@lines){

            if ($line =~ /bcaseb/)

            {

                $caselang   = $line =~ /blangb/i;

            }



            if ($line =~ /bbreakb/)

            {

                $caselang   = 0;

            }



            if ($caselang)

            {

                print "old $linen";

                $line       =~ s/ == 2/ >= 2/;

                $line       =~ s/strtolower(.value)/strtolower(substr($value,0,2))/;

                $updated    = 1;

                print "new $linen";

            }

        }



        if ($updated)

        {

            # my $newfile   = $File::Find::dir . "/" . $_;

            my $newfile     = $odir . $_;

            print "alter $lang to support ll-CC $newfilen";

            write_file($newfile, @lines);

        }

        else

        {

            print "did not find lang support in $_n";

        }



    }

    return;

}

The first match replace works, to change the == to >=, but the second match replace does not modify any lines and I do not understand well. I thought maybe there was a problem with matching to "$" so I replaced it with "." but still no lines are changed. I applied the same command to other regex engines and they all worked. The output for a typical file is:

wanted: /home/jcobban/public_html/videoTutorials.php

odir '/home/jcobban/testlang/'

old         case 'lang':

new         case 'lang':

old         {

new         {

old             if (strlen($value) == 2)

new             if (strlen($value) >= 2)

old                 $lang       = strtolower($value);

new                 $lang       = strtolower($value);

alter $lang to support ll-CC /home/jcobban/testlang/videoTutorials.php

I have obviously been spending too much time using VIM. The problem with my code was that I needed to escape the round brackets so they were not interpreted as a subpattern.

    $line       =~ s/strtolower(.value)/strtolower(substr($value,0,2))/;

Just want to show some hacks, maybe it will be interesting for you:

s'strtolower(K$value'substr($value,0,2)'

We can quote substitution with whatever we want:

s/foo/bar/;

s'foo'bar';

s(foo)(bar);

If we choose single quotes, variables will not be interpolated, but we still have to escape dollar sign in pattern side, because it will be treated as "end of line" by re engine.

K Keep the stuff left of the K

more information in perldoc perlre