Perl regexp substitution problem

works an an m{} but not as an s{}{}

[dingman]

I'm beating my head against what I think is a simple Perl issue. I'm trying to munge data into a reasonably presentable form, and the last thing left is to translate "<tr><th>Location:</th><td> wsl</td></tr>" to "<tr><th>Location:</th><td> Workshop Research Library</td></tr>". I'm trying to do this with the line:

$bib =~ s{(Location:</th><td>)\s?(wsl)}{$1 Workshop Research Library}isg;

I added the line
if ($bib =~ m{(Location:</th><td>)\s?(wsl)}is) {print STDERR "$1$2\n";}
to my script to confirm that the expression truly is matching what it's supposed to, and the output I get with that line in place looks like the expression works. Can anyone help me figure out why the substitution doesn't work?

-dingman

[volatilegx]

Just use:

$bib =~ s/<td> wsl<\/td>/<td> Workshop Research Library<\/td>/ig;

[andreasfriedrich]

I just tested your substitution with

perl -e ' 
$_="<tr><th>Location:</th><td> wsl</td></tr>"; 
s{(Location:</th><td>)\s?(wsl)}{$1 Workshop Research Library}isg; 
print $_;'

It worked. The output was:

<tr><th>Location:</th><td> Workshop Research Library</td></tr>

[dingman]

Thanks for the snippet, but it's not working, either. Any idea what was wrong with mine? I'd like to actually learn something from this rather than merely steal a line of code.

-dingman

[volatilegx]

Weird... my snippet works on my server.

Are you able to do other substitutions?

Does either snippet cause server errors or does the substitution just not work?

[andreasfriedrich]

Which one is not working either?

Have you tried it from the prompt?

Would you mind posting some more code surrounding the problematic line?

Are you sure that $bib contains the same string when you try the substitution and when you do the matching?

Since my code was working for me on my box IŽm assuming the error must be somewhere else.

What perl version are you running?

[dingman]

andreas, what version of Perl are you using? The two machines I've just tried this on are using perl 5.6.0 and 5.6.1, and neither of them performs that substitution. It's one of dozens in the script, and also the last one before a 'return', after which nothing happens but printing the output. All the others work as designed.

I should also have been a bit more clear that some of the occurances have a <br> after wsl in the original $bib - hence the fact that I was not matching on anything after wsl. I don't have much control over the input, so I have to just deal with that.

-dingman

[andreasfriedrich]

Summary of my perl5 (revision 5.0 version 6 subversion 0) configuration: 
 Platform: 
 osname=linux, osvers=2.2.17-8smp, archname=i386-linux 
 uname='linux porky.devel.redhat.com 2.2.17-8smp 
 #1 smp fri nov 17 16:12:17 est 2000 i686 unknown ' 
 config_args='-des -Doptimize=-O2 -march=i386 -mcpu=i686 
 -Dcc=gcc -Dcccdlflags=-fPIC -Dinstallprefix=/usr 
 -Dprefix=/usr -Darchname=i386-linux -Dd_dosuid 
 -Dd_semctl_semun -Di_db -Di_ndbm -Di_gdbm -Di_shadow 
 -Di_syslog -Dman3ext=3pm -Uuselargefiles' 
 hint=recommended, useposix=true, d_sigaction=define 
 usethreads=undef use5005threads=undef useithreads=undef 
 usemultiplicity=undef 
 useperlio=undef d_sfio=undef uselargefiles=undef  
 use64bitint=undef use64bitall=undef uselongdouble=undef usesocks=undef 
 Compiler: 
 cc='gcc', optimize='-O2 -march=i386 -mcpu=i686', gccversion=2.96 20000731 
  (Red Hat Linux 7.1 2.96-78) 
 cppflags='-fno-strict-aliasing' 
 ccflags ='-fno-strict-aliasing' 
 stdchar='char', d_stdstdio=define, usevfork=false 
 intsize=4, longsize=4, ptrsize=4, doublesize=8 
 d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12 
 ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', 
 lseeksize=4 
 alignbytes=4, usemymalloc=n, prototype=define 
 Linker and Libraries: 
 ld='gcc', ldflags =' -L/usr/local/lib' 
 libpth=/usr/local/lib /lib /usr/lib 
 libs=-lnsl -ldl -lm -lc -lcrypt 
 libc=/lib/libc-2.2.so, so=so, useshrplib=false, libperl=libperl.a 
 Dynamic Linking: 
 dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-rdynamic' 
 cccdlflags='-fPIC', lddlflags='-shared -L/usr/local/lib' 
Characteristics of this binary (from libperl):  
 Compile-time options: 
 Built under linux 
 Compiled at Apr 3 2001 11:27:33 
 @INC: 
 /usr/lib/perl5/5.6.0/i386-linux 
 /usr/lib/perl5/5.6.0 
 /usr/lib/perl5/site_perl/5.6.0/i386-linux 
 /usr/lib/perl5/site_perl/5.6.0 
 /usr/lib/perl5/site_perl 
 .

[dingman]

#translate a location of "wsl" to "Workshop Research Library"
#if ($bib =~ m{(Location:</th><td>)\s?(wsl)}is) {print STDERR "$1$2\n";}
$bib =~ s{(Location:</th><td>)\s?(wsl)}{$1 Workshop Research Library}isg;

$entry = "<html>\n\t<head>\n\t\t<title> $author\t$date\t$title</title>";
$entry .= "<link rel=\"stylesheet\" type=\"text/css\" ";
$entry .= "href=\"http://www.indiana.edu/~iascp/CSS/cprbib.css\">\n\t</head>\n";
$entry .= "\t<body>\n<table>\n$bib\n</table>\n</body>\n<!-- EndLogicalDocument -->\n";

return $entry;
}

I'll hapily post the whole 9k script somewhere you can download it if you're interested.

-dingman

[dingman]

BTW, I don't doubt that it's my fault, and I really do appreciate your help. Having tested at the command prompt with just that substitution, it does seem to work as advertised *outside* of my script.

[andreasfriedrich]

Are you running this as a stand alone perl script or under mod_perl?

I just tested the substitution with perl 5.6.1 for Windows and it was working as well.

If youŽd send me the script using the address in my profile I'll gladly try to run your script either as a stand alone script or mod_perl module.

Andreas

[dingman]

It's a stand-alone perl script that generates a file of hundreds of HTML documents concatenated together, and then a search engine sorts out which one you the user wants.

I think I might have just found my bone-head error. If not, I introduced a new one...

-dingman

[dingman]

I'm an embarassed idiot. There were <p>s around wsl and I didn't even see them in the output I was staring at.

Thanks for humoring me. I finally saw the <p> tags while I was composing an e-mail to Andreas in an adjacent window.

-dingman