Personally I'd parse it into a data structure first, and then use that data structure to generate the output:

use Modern::Perl;
use String::Trim;
use Data::Dumper;
$Data::Dumper::Sortkeys = 1;
$Data::Dumper::Terse    = 1;

my @rows;
while (<DATA>)
{
    chomp;
    trim;
    
    my @F = split /\s*=\s*/;
    
    push @rows, [map {
        my %x = (field => $F[$_ - 1], value => $F[$_]);
        $x{field} =~ s/.*\s+(\S+)$/$1/ unless $_ == 1;
        $x{value} =~ s/\s*\S+$// unless $_ == $#F;
        \%x;
    } 1 .. $#F];
}

print Dumper \@rows;

for (@rows)
{
    say join q(,), map { $_->{value} } @$_;
}

__DATA__
FIELDA = ONEAL FIELDB = RELAY FIELDC = L1208 FIELDD = ALTS
FIELDA = OSSIPEE FIELDB = DISC FIELDC = SOH: 169879251 FIELDD = DISC
FIELDA = OSSIPEE FIELDB = RELAY FIELDC = L1201 FIELDD = ALTS
FIELDA = OSSIPEE FIELDB = RELAY FIELDC = L1203 FIELDD = ALTS

[download]
perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

In reply to Re: How to improve regex for parsing equals delimited data by tobyink
in thread How to improve regex for parsing equals delimited data by Lotus1

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