Perl: Replace strings in multiple files with array entry - arrays

Question

I am looking for a simple way to replace strings in multiple text files. In the first file the string should be replaced with the first element of the array #arrayF; in the second file the string must be replaced with the second entry etc.
I want to replace ;size=\d+ where \d+ is a wildcard for any number.
This is what I have so far:
#!/usr/bin/perl -w
use strict;
use warnings;
my $counter = 0;
my #arrayF = '/Users/majuss/Desktop/filelist.txt>'; # Reads all lines into array
my #files = '/Users/majuss/Desktop/New_Folder/*'; #get Files into an array
foreach my $file ( #files ) {
$file =~ s/;size=\d+/$arrayF[$counter]/g; #subst.
print
$counter++; #increment array index
}
It gives a zero back and nothing happens.
I know how to do it in a one-liner but I can't figure a way out how to implement an array there.

Answer 1

Note these points that I commented on beneath your question
The line commented Reads all lines into array doesn't do that. It simply sets #arrayF to a one-element list that holds the string /Users/majuss/Desktop/filelist.txt>. You probably need to open the file and read its contents into an array
The line commented get Files into an array doesn't do that. It simply sets #files to a one-element list that holds the string /Users/majuss/Desktop/New_Folder/*. You probably need to use glob to expand the wildcard into a list of files
The statement
$file =~ s/;size=\d+/$arrayF[$counter]/g
is attempting to modify the variable $file which contains the name of the file. Presumably you meant to edit the contents of that file, so you must open and read it first
Please don't use upper-case letters in your local identifiers
Don't use -w on the shebang line as well as use warnings; just the latter is correct
This seems to do what you're asking for, but be aware that it is untested except that I have checked that it will compile. Be careful that you have a backup of the original files as this code will overwrite the original files with the modified data
#!/usr/bin/perl
use strict;
use warnings;
use 5.010;
use autodie;
my $replacement_text = '/Users/majuss/Desktop/filelist.txt';
my $file_glob = '/Users/majuss/Desktop/New_Folder/*';
my #replacement_text = do {
open my $fh, '<', $replacement_text;
<$fh>;
};
chomp #replacement_text;
my $i = 0;
for my $file ( glob $file_glob ) {
my $contents = do {
open my $in_fh, '<', $file;
local $/;
<$in_fh>;
};
$contents =~ s/;size=\d+/$replacement_text[$i]/g;
open my $out_fh, '>', $file;
print $out_fh $contents;
++$i;
}

Answer 2

You're not opening filelist.txt and reading it.
Do do this you need to:
open ( my $input, "<", '/Users/majuss/Desktop/filelist.txt' ) or die $!;
my #arrayF = <$input>;
close ( $input );
You need to use glob to search a directory pattern like that.
Like this:
foreach my $file ( glob ( '/Users/majuss/Desktop/New_Folder/*' ) {
# stuff
}
To search and replace within a file, it's actually a bit different to a one liner. You can look at 'in place editing' in perlrun - but this is where perl is trying to pretend to be sed. I think you can do it if you try - there's an option in perlvar:
$^I
The current value of the inplace-edit extension. Use undef to disable inplace editing.
Mnemonic: value of -i switch.
This answer may give some insight:
In-place editing of multiple files in a directory using Perl's diamond and in-place edit operator
Instead you can:
foreach my $file ( glob ( '/Users/majuss/Desktop/New_Folder/*' ) {
open ( my $input_fh, "<", $file ) or die $!;
open ( my $output_fh, ">", "$file.NEW" ) or die $!;
my $replace = shift ( #arrayF );
while ( my $line = <$input_fh> ) {
$line =~ s/;size=\d+/$replace/g;
print {$output_fh} $line;
}
close ( $input_fh );
close ( $output_fh );
#rename 'output'.
}