#118 RTU/PLC code cleanup

rtu/dev/boilerv_rtu.lua

@@ -3,6 +3,7 @@ local rtu = require("rtu.rtu")
 local boilerv_rtu = {}
 
 -- create new boiler (mek 10.1+) device
+---@nodiscard
 ---@param boiler table
 function boilerv_rtu.new(boiler)
     local unit = rtu.init_unit()

rtu/dev/envd_rtu.lua

@@ -3,6 +3,7 @@ local rtu = require("rtu.rtu")
 local envd_rtu = {}
 
 -- create new environment detector device
+---@nodiscard
 ---@param envd table
 function envd_rtu.new(envd)
     local unit = rtu.init_unit()

rtu/dev/imatrix_rtu.lua

@@ -3,6 +3,7 @@ local rtu = require("rtu.rtu")
 local imatrix_rtu = {}
 
 -- create new induction matrix (mek 10.1+) device
+---@nodiscard
 ---@param imatrix table
 function imatrix_rtu.new(imatrix)
     local unit = rtu.init_unit()

rtu/dev/redstone_rtu.lua

@@ -1,7 +1,7 @@
-local rtu  = require("rtu.rtu")
-
 local rsio = require("scada-common.rsio")
 
+local rtu  = require("rtu.rtu")
+
 local redstone_rtu = {}
 
 local IO_LVL = rsio.IO_LVL
@@ -10,14 +10,15 @@ local digital_read = rsio.digital_read
 local digital_write = rsio.digital_write
 
 -- create new redstone device
+---@nodiscard
 function redstone_rtu.new()
     local unit = rtu.init_unit()
 
     -- get RTU interface
     local interface = unit.interface()
 
+    -- extends rtu_device; fields added manually to please Lua diagnostics
     ---@class rtu_rs_device
-    --- extends rtu_device; fields added manually to please Lua diagnostics
     local public = {
         io_count = interface.io_count,
         read_coil = interface.read_coil,

rtu/dev/sna_rtu.lua

@@ -2,7 +2,8 @@ local rtu = require("rtu.rtu")
 
 local sna_rtu = {}
 
--- create new solar neutron activator (sna) device
+-- create new solar neutron activator (SNA) device
+---@nodiscard
 ---@param sna table
 function sna_rtu.new(sna)
     local unit = rtu.init_unit()

rtu/dev/sps_rtu.lua

@@ -2,7 +2,8 @@ local rtu = require("rtu.rtu")
 
 local sps_rtu = {}
 
--- create new super-critical phase shifter (sps) device
+-- create new super-critical phase shifter (SPS) device
+---@nodiscard
 ---@param sps table
 function sps_rtu.new(sps)
     local unit = rtu.init_unit()

rtu/dev/turbinev_rtu.lua

@@ -3,6 +3,7 @@ local rtu = require("rtu.rtu")
 local turbinev_rtu = {}
 
 -- create new turbine (mek 10.1+) device
+---@nodiscard
 ---@param turbine table
 function turbinev_rtu.new(turbine)
     local unit = rtu.init_unit()