#!/usr/bin/perl
use strict;
use warnings;
# 783199

my @data = <DATA>; 

for my $line (@data) {
	chomp $line;
#	if ( $line =~ /[<>@#\$%^&*()_+=|\{\}\[\]\/\\]/ ) {    # OP's char class ie "escaped the $ sign"
#	if ( $line =~ /[<>@#%^&*()_+=|\{\}\[\]\/\\]\$/ ) {    # OP's char class ie "escaped the $ sign" with \$ moved to end of class
#	if ( $line =~ /[<>@#$%^&*()_+=|\{\}\[\]\/\\]/) {      # $ sign not backslashed
#	if ( $line =~ /[<>@#\$%^&*()_+=|{}\]\/\\]/ ) {        # unnecessary backslashes removed
    if ( $line =~ /[0-9<>@#\$%^&*()_+=|{}[\]\/\\]/ ) { 		  # rule out decimal digits
    	print "\$line: $line \t is not okay \n";
	}else {
    	print "\$line: $line \t is okay \n";
	}
}

=head

$ sign in char class preceded by a backslash
$line: hello there0      is okay
$line: hello there       is okay
$line: hello there$ now          is not okay
$line: hello there $ now         is not okay
$line: hello there [     is not okay
$line: by [rights] this should fail.     is not okay
 
$ sign in char class NOT preceded by a backslash
$line: hello there0      is not okay
$line: hello there       is okay
$line: hello there$ now          is okay
$line: hello there $ now         is okay
$line: hello there [     is not okay
$line: by [rights] this should fail.     is not okay

Unnecessary backslashes removed:
$line: hello there0      is okay
$line: hello there       is okay
$line: hello there$ now          is not okay
$line: hello there $ now         is not okay
$line: hello there [     is okay
$line: by [rights] this should fail.     is not okay

and with Decimal Digits rejected:
$line: hello there0      is not okay
$line: hello there       is okay
$line: hello there$ now          is not okay
$line: hello there $ now         is not okay
$line: hello there [     is not okay
$line: by [rights] this should fail.     is not okay
=cut

__DATA__
hello there0
hello there
hello there$ now
hello there $ now
hello there [
by [rights] this should fail.