What are you trying to do specifically?
You can use $ialchan() to find host on a given channel, if you want to know which host from a given channel A is also on a given channel B, you can just use a while loop:
Code:
alias checkhosts {
  var %A $1,%B $2,%i 1,%m
  while ($ialchan(*,%A,%i) != $null) {
    %m = $v1
    if ($ialchan(%m,%B,0)) {
    echo -a host %m on %A is also on %B -- nick on %A : $ialchan(%m,%A,1).nick -- nick on %B : $ialchan(%m,%B,1).nick
    }
    inc %i
  }
}
Type /checkhosts #channelA #channelB

Note that multiple nickname could belong to a given host, the code will only return the first one.

Edit: looks like you were talking about another kind of 'host' grin

Last edited by Wims; 11/09/15 12:55 PM.
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