Syntax smile

/ignore [-lrpcntikdwxu#] <on|off|nick/address> [type] [network]
Where p = private, c = channel, n = notice, t = ctcp, i = invite, k = control codes, d = dccs

There is no $chan parameter.
To ignore what the user says in channels, use the -c switch.
Code:
/temp_ignore ignore $+(-[color:blue]c[/color]u,$1) $2 8