nginx hack for multiple conditions

nginx.conf

    if ($request_uri = /) { 
      set $test  A; 
    } 
  
    if ($host ~* teambox.com) { 
      set $test  "${test}B"; 
    } 
  
    if ($http_cookie !~* "auth_token") { 
      set $test  "${test}C"; 
    } 
    
    if ($test = ABC) { 
      proxy_pass http://teambox-cms.heroku.com; 
      break; 
    } 


for or condition

set $my_var 0;
if ($host = 'domain.com') {
  set $my_var 1;
}
if ($host = 'domain2.com') {
  set $my_var 1;
}
if ($my_var = 1) {
  rewrite ^/(.*)$ http://www.domain.com/$1 permanent;
}