Hello, I'd appreciate any guidance on this -- I'm very new to PERL and can't crack this one. I have a pipe delimited file and the beginning of each line must start with | and end with || (no space in-between). Blank columns on a row should have a space inbetween the delimiters | |. I created the code below using regex to insert a space between the || delimiters anywhere a column might have blank data which is working ok.

Here's an example, the code below changes the file from:

|red||blue|yellow||black||

|white|yellow||teal||purple||

|red||black||yellow||teal||

To..(note spaces between delimiters for blank column data)

|red| |blue|yellow| |black||

|white|yellow| |teal| |purple||

|red| |black|yellow| |teal||

Here's the code

#!C:\Perl64\bin\perl -w

use strict;

# Iteration 1, open myfile.txt

open(FILE, "</temp/PERL-Samples/myfile.txt") || die "File not found";
my @lines = <FILE>;
close(FILE);

#This section uses an array and scans each line and does a 
#sequential search and replace for the following strings:
#1. Finds any instance of || and changes it to | |
#2. Finds any instance of | || and changes it to | | |
#3. Finds any instance of || | and changes it to | | |
#4. Finds any instance of | | at the end of a line and 
#changes it to ||

my @newlines;
foreach(@lines) {
   $_ =~ s/\|\|/\| \|/g;
   $_ =~ s/\| \|\|/\| \|/g;
   $_ =~ s/\|\| \|/\| \|/g;
   $_ =~ s/\| \|$/\|\|/g;
   push(@newlines,$_);
}

#Push changes to MyFileNew.dat

open(FILE, ">/temp/PERL-Samples/MyFileNew.dat") || die "File not found
+";
print FILE @newlines;
close(FILE);
[download]

Another pre-existing condition this file has is there are several hundred lines where | and || exist on a line by themselves. Plus there are other lines not beginning with a | and ending with ||. For example:

|red| |blue|yellow| |black

||

|white|yellow| |teal| |purple||

|

red| |black|yellow| |teal

||

I'm not sure how to reliably and efficiently delete rows where || and | are the only characters in a line and also make sure each line is prefixed with | and suffixed with ||. Thanks in advance for reviewing this.

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