function IsUnitGroupEmptyBJ takes group g returns boolean
    // If the user wants the group destroyed, remember that fact and clear
    // the flag, in case it is used again in the callback.
    local boolean wantDestroy = bj_wantDestroyGroup
    set bj_wantDestroyGroup = false

    set bj_isUnitGroupEmptyResult = true
    call ForGroup(g, function IsUnitGroupEmptyBJEnum)

    // If the user wants the group destroyed, do so now.
    if (wantDestroy) then
        call DestroyGroup(g)
    endif
    return bj_isUnitGroupEmptyResult
endfunction

function IsUnitGroupEmptyBJEnum takes nothing returns nothing
    set bj_isUnitGroupEmptyResult = false
endfunction

function IsGroupEmpty takes group g returns boolean
  return FirstOfGroup(g) == null
endfunction