The following gives the output you want with the provided example: 

#!/usr/bin/env perl

use 5.010;
use strict;
use warnings;

my $cmd = '&COMPAREEQUAL(First-param.one, Second.param,Third-param)';

my $cms_re = qr{
    (?: [&( ] )?
    (
        [^(), ]+
    )
    (?: [(,)] )?
}x;

say for $cmd =~ m{$cms_re}g;

[download]

Output: 

$ pm_cmd_args_regex.pl
COMPAREEQUAL
First-param.one
Second.param
Third-param

[download]

-- Ken

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

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