FiveM entity iterators

entityiter.lua

--[[The MIT License (MIT)

Copyright (c) 2017 IllidanS4

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
]]

local entityEnumerator = {
  __gc = function(enum)
    if enum.destructor and enum.handle then
      enum.destructor(enum.handle)
    end
    enum.destructor = nil
    enum.handle = nil
  end
}

local function EnumerateEntities(initFunc, moveFunc, disposeFunc)
  return coroutine.wrap(function()
    local iter, id = initFunc()
    if not id or id == 0 then
      disposeFunc(iter)
      return
    end
    
    local enum = {handle = iter, destructor = disposeFunc}
    setmetatable(enum, entityEnumerator)
    
    local next = true
    repeat
      coroutine.yield(id)
      next, id = moveFunc(iter)
    until not next
    
    enum.destructor, enum.handle = nil, nil
    disposeFunc(iter)
  end)
end

function EnumerateObjects()
  return EnumerateEntities(FindFirstObject, FindNextObject, EndFindObject)
end

function EnumeratePeds()
  return EnumerateEntities(FindFirstPed, FindNextPed, EndFindPed)
end

function EnumerateVehicles()
  return EnumerateEntities(FindFirstVehicle, FindNextVehicle, EndFindVehicle)
end

function EnumeratePickups()
  return EnumerateEntities(FindFirstPickup, FindNextPickup, EndFindPickup)
end

--[[Usage:
for ped in EnumeratePeds() do
  <do something with 'ped'>
end
]]