Perl

String replacement in a file

Please support our Perl advertiser: Programming Forums - DaniWeb Sister Site

•

Join Date: Feb 2005

Posts: 78

Reputation: nanodano is an unknown quantity at this point

Solved Threads: 2

nanodano

Offline

Junior Poster in Training

String replacement in a file

Apr 4th, 2007

I have a very specific problem.

Does s/// work with strings that are contained in single quotes? I've been debugging and I'm trying to replace a string that contains a $ in it. If I use double quotes, it works for the string up until the $. If I use single quotes, it does not work with any string.

Here is my code; it involves file access, and file.data contains the string "testing $my string."

 Help with Code Tags 
 Perl Syntax (Toggle Plain Text) 
#!/usr/bin/perl
 
$s1 = "testing $my string";
$s2 = "testing $your string";
 
local ($^I, @ARGV) = ('.bak', 'file.data');
while (<>) {
        s/$s1/$s2/g;
  print;
}
#!/usr/bin/perl

$s1 = "testing $my string";
$s2 = "testing $your string";

local ($^I, @ARGV) = ('.bak', 'file.data');
while (<>) {
        s/$s1/$s2/g;
  print;
}

•

Join Date: Mar 2006

Posts: 898

Reputation: KevinADC has a spectacular aura about

Solved Threads: 67

KevinADC

Offline

Practically a Posting Shark

Re: String replacement in a file

Apr 4th, 2007

 Help with Code Tags 
 Perl Syntax (Toggle Plain Text) 
#!/usr/bin/perl
 
$s1 = "testing $my string";
$s2 = "testing \$your string";
 
local ($^I, @ARGV) = ('.bak', 'file.data');
while (<>) {
        s/\Q$s1\E/$s2/g;
  print;
}
#!/usr/bin/perl

$s1 = "testing $my string";
$s2 = "testing \$your string";

local ($^I, @ARGV) = ('.bak', 'file.data');
while (<>) {
        s/\Q$s1\E/$s2/g;
  print;
}

•

Join Date: Feb 2005

Posts: 78

Reputation: nanodano is an unknown quantity at this point

Solved Threads: 2

nanodano

Offline

Junior Poster in Training

Re: String replacement in a file

Apr 5th, 2007

I added an escape \ to $s1 like you did to $s2 and it worked great, thanks!

•

Join Date: Mar 2006

Posts: 898

Reputation: KevinADC has a spectacular aura about

Solved Threads: 67

KevinADC

Offline

Practically a Posting Shark

Re: String replacement in a file

Apr 5th, 2007

Ahh, now that I think about it \Q does not affect $ in a regexp, so you would use the quotemeta() function or add the escape character manually like you did.