dfhack/scripts/fix/dead-units.lua

-- Remove uninteresting dead units from the unit list.
--[[=begin

fix/dead-units
==============
Removes uninteresting dead units from the unit list. Doesn't seem to give any
noticeable performance gain, but migrants normally stop if the unit list grows
to around 3000 units, and this script reduces it back.

=end]]
local units = df.global.world.units.active
local dwarf_race = df.global.ui.race_id
local dwarf_civ = df.global.ui.civ_id
local count = 0

for i=#units-1,0,-1 do
    local unit = units[i]
    local flags1 = unit.flags1
    local flags2 = unit.flags2
    if flags1.dead and unit.race ~= dwarf_race then
        local remove = false
        if flags2.slaughter then
            remove = true
        elseif not unit.name.has_name then
            remove = true
        elseif unit.civ_id ~= dwarf_civ and
               not (flags1.merchant or flags1.diplomat) then
            remove = true
        end
        if remove then
            count = count + 1
            units:erase(i)
        end
    end
end

print('Units removed from active: '..count)