Hello, received the following fatal error while clicking on a conveyor belt to build:

Error while running event SchallRechargingWeapon::on_player_cursor_stack_changed (ID 29)
real number expected got nil.
stack traceback:
SchallRechargingWeapon/control.lua:98: in function 'main_inventory_clear_ammo'
SchallRechargingWeapon/control.lua:127: in function <SchallRechargingWeapon/control.lua:126>
stack traceback:
[C]: in function 'get_inventory'
SchallRechargingWeapon/control.lua:98: in function 'main_inventory_clear_ammo'
SchallRechargingWeapon/control.lua:127: in function <SchallRechargingWeapon/control.lua:126>

It is due to the big internal changes from version 0.17.35 update.
I will try updating all my mods on these days, or you can downgrade game to 0.17.34 if you don't want to wait.

Patch to support 0.17.35:

diff -urN SchallRechargingWeapon_0.17.4/changelog.txt SchallRechargingWeapon_0.17.5/changelog.txt
--- SchallRechargingWeapon_0.17.4/changelog.txt 2019-04-19 09:06:43.782645200 +1000
+++ SchallRechargingWeapon_0.17.5/changelog.txt 2019-05-04 11:02:38.573453900 +1000
@@ -1,4 +1,9 @@
 ---------------------------------------------------------------------------------------------------
+Version: 0.17.5
+Date: 2019.05.04
+  Bugfixes:
+    - Support for 0.17.35
+---------------------------------------------------------------------------------------------------
 Version: 0.17.4
 Date: 2019.04.19
   Features:
diff -urN SchallRechargingWeapon_0.17.4/control.lua SchallRechargingWeapon_0.17.5/control.lua
--- SchallRechargingWeapon_0.17.4/control.lua   2019-03-22 21:59:44.902814200 +1100
+++ SchallRechargingWeapon_0.17.5/control.lua   2019-05-04 10:22:14.915656900 +1000
@@ -24,9 +24,9 @@

 local function recharge_weapons(e)
   local player = game.players[e.player_index]
-  local gun = player.get_inventory(defines.inventory.player_guns)
+  local gun = player.get_inventory(defines.inventory.character_guns)
   if not gun then return end
-  local ammo = player.get_inventory(defines.inventory.player_ammo)
+  local ammo = player.get_inventory(defines.inventory.character_ammo)
   local recharge_guns = {}
   local non_recharge_guns = {}
   local ammoname
@@ -95,7 +95,7 @@

 local function main_inventory_clear_ammo(e)
   local player = game.players[e.player_index]
-  local maininv = player.get_inventory(defines.inventory.player_main)
+  local maininv = player.get_main_inventory()
   if not maininv then return end
   local num
   for ammo,v in pairs(recharge_charges) do
diff -urN SchallRechargingWeapon_0.17.4/info.json SchallRechargingWeapon_0.17.5/info.json
--- SchallRechargingWeapon_0.17.4/info.json 2019-04-19 08:34:54.514407200 +1000
+++ SchallRechargingWeapon_0.17.5/info.json 2019-05-04 11:02:00.676219800 +1000
@@ -1,6 +1,6 @@
 {
   "name": "SchallRechargingWeapon",
-  "version": "0.17.4",
+  "version": "0.17.5",
   "title": "Schall Recharging Weapon",
   "author": "Schallfalke",
   "email": "",
@@ -8,5 +8,5 @@
   "contact": "",
   "description": "Experimental recharge mechanism.  Introduced energy weapons, which recharge from personal batteries!\nCurrently includes laser rifle, laser sniper rifle, laser shotgun, laser machine gun, mega laser cannon, chainsaw.",
   "factorio_version": "0.17",
-  "dependencies": ["base >= 0.17.0", "? SchallPrimaryBattery"]
-}
\ No newline at end of file
+  "dependencies": ["base >= 0.17.35", "? SchallPrimaryBattery"]
+}

Thanks for the prompt responses! (and a patch, too!)

Should be fixed in recent version 0.17.5.
And thanks mrudat for making the patch. (I didn't have the time to sit in front of my home computer last days.)