Isn't split easier? 
my $cmd = q|&COMPAREEQUAL(First-param.one, Second.param,Third-param)|;
if ($cmd =~ /^&([^(]+)\(([^)]+)\)$/) {
 my $sub = $1;
 my @args = split /,\s*/,$2;
 print Dumper [ $sub, \@args ];
}
__END__
$VAR1 = [
          'COMPAREEQUAL',
          [
            'First-param.one',
            'Second.param',
            'Third-param'
          ]
        ];

[download]
</c>
Sorry if my advice was wrong.

In reply to Re: regex extraction for variable number of args by aitap
in thread regex extraction for variable number of args by NetWallah

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