My Version:

alias ieif {
  var %x = 1, %b
  while (%x <= $0) {
    %b = $($ $+ %x,2)
    if (2 \\ $0) && ($calc($0 - 2) == %x) {
      return $iif( [ %b ] , [ $(,$ $+ $calc(%x +1),2) ] , [ $(,$ $+ $calc(%x +2),2) ] )
    }
    $iif( [ %b ] ,return [ $(,$ $+ $calc(%x +1),2) ] , inc %x 2)
  }
}

Usage: Same as $iif() except it allows for multiple elseifs.
IE: $ieif(a == a,a,b == b,b,c)

Issues/Bugs:
For things you want evaluated from within the $ieif() you must $(...,0) those items(such as $v1 and $v2)
For things you don't want evaluated at all, you must double escape them. IE: $ieif(a == a,$($!me is testing,0))

Fixes: Fixed the elsepart not evaluting $v1/$v2/$ifmatch/$ifmatch2 properly