Ensure returned numbers are of type number

Thanks to Felix for bringing this to my attention. Obviously there was
already a safety net for feeding progressbars and graphs... and while
this makes for a good coding practice it's not a big deal. We have
widgets of type textbox for one, and a lot of string concatenation
happens. Strings are formatted, markup is applied...

bat.lua

@@ -36,13 +36,13 @@ local function worker(format, batid)
     -- Get /proc/acpi/battery info
     local f = io.open("/proc/acpi/battery/"..batid.."/info")
     -- Handler for incompetent users
-    if not f then return {battery_state["unknown"], "0", "N/A"} end
+    if not f then return {battery_state["unknown"], 0, "N/A"} end
     local infofile = f:read("*all")
     f:close()
 
     -- Check if the battery is present
     if infofile == nil or string.find(infofile, "present:[%s]+no") then
-        return {battery_state["unknown"], "0", "N/A"}
+        return {battery_state["unknown"], 0, "N/A"}
     end
 
     -- Get capacity information

batat.lua

@@ -4,6 +4,7 @@
 ---------------------------------------------------
 
 -- {{{ Grab environment
+local tonumber = tonumber
 local io = { popen = io.popen }
 local setmetatable = setmetatable
 local table = { insert = table.insert }
@@ -34,11 +35,11 @@ local function worker(format)
         if string.match(line, "^[%s]+Battery.*") then
             -- Store state and charge information
             table.insert(battery_info, (battery_state[string.match(line, "([%a]*),") or "unknown"]))
-            table.insert(battery_info, (string.match(line, "([%d]?[%d]?[%d])%.") or "0"))
+            table.insert(battery_info, (tonumber(string.match(line, "([%d]?[%d]?[%d])%.")) or 0))
             -- Store remaining time information
             table.insert(battery_info, (string.match(line, "%%,%s(.*)") or "N/A"))
         else
-            return {battery_state["unknown"], "0", "N/A"}
+            return {battery_state["unknown"], 0, "N/A"}
         end
     end
     f:close()

cpufreq.lua

@@ -4,6 +4,7 @@
 ---------------------------------------------------
 
 -- {{{ Grab environment
+local tonumber = tonumber
 local io = { open = io.open }
 local setmetatable = setmetatable
 local string = {
@@ -45,7 +46,7 @@ local function worker(format, cpuid)
     local f = io.open("/sys/devices/system/cpu/"..cpuid.."/cpufreq/scaling_voltages")
     if f then for line in f:lines() do
         if string.find(line, "^"..freq) then
-            voltage.mv = string.match(line, "[%d]+[%s]([%d]+)")
+            voltage.mv = tonumber(string.match(line, "[%d]+[%s]([%d]+)"))
             break
         end
       end

cpuinf.lua

@@ -26,13 +26,13 @@ local function worker(format)
         if string.match(line, "^processor.*") then
             cpu_id = string.match(line, "([%d]+)")
         elseif string.match(line, "^cpu MHz.*") then
-            local cpu_speed = string.match(line, "([%d]+)%.")
+            local cpu_speed = tonumber(string.match(line, "([%d]+)%."))
             cpu_info["{cpu"..cpu_id.." mhz}"] = cpu_speed
-            cpu_info["{cpu"..cpu_id.." ghz}"] = tonumber(cpu_speed) / 1000
+            cpu_info["{cpu"..cpu_id.." ghz}"] = cpu_speed / 1000
         elseif string.match(line, "^cache size.*") then
-            local cpu_cache = string.match(line, "([%d]+)[%s]KB")
+            local cpu_cache = tonumber(string.match(line, "([%d]+)[%s]KB"))
             cpu_info["{cpu"..cpu_id.." kb}"] = cpu_cache
-            cpu_info["{cpu"..cpu_id.." mb}"] = tonumber(cpu_cache) / 1024
+            cpu_info["{cpu"..cpu_id.." mb}"] = cpu_cache / 1024
         end
     end
     f:close()

entropy.lua

@@ -4,6 +4,7 @@
 ---------------------------------------------------
 
 -- {{{ Grab environment
+local tonumber = tonumber
 local io = { open = io.open }
 local setmetatable = setmetatable
 local math = { ceil = math.ceil }
@@ -21,7 +22,7 @@ local function worker(format, poolsize)
 
     -- Get available entropy
     local f = io.open("/proc/sys/kernel/random/entropy_avail")
-    local ent = f:read("*line")
+    local ent = tonumber(f:read("*line"))
     f:close()
 
     -- Calculate percentage

fs.lua

@@ -5,6 +5,7 @@
 ---------------------------------------------------
 
 -- {{{ Grab environment
+local tonumber = tonumber
 local io = { popen = io.popen }
 local setmetatable = setmetatable
 local string = { match = string.match }
@@ -30,10 +31,10 @@ local function worker(format, nfs)
              -- Match all at once, including network file systems
              string.match(line, "^[%w%p]+[%s]+([%d%.]+)[%a]?[%s]+([%d%.]+)[%a]?[%s]+([%d%.]+)[%a]?[%s]+([%d]+)%%[%s]+([%w%p]+)$")
 
-            fs_info["{"..mount.." size}"]  = size
-            fs_info["{"..mount.." used}"]  = used
-            fs_info["{"..mount.." avail}"] = avail
-            fs_info["{"..mount.." usep}"]  = usep
+            fs_info["{"..mount.." size}"]  = tonumber(size)
+            fs_info["{"..mount.." used}"]  = tonumber(used)
+            fs_info["{"..mount.." avail}"] = tonumber(avail)
+            fs_info["{"..mount.." usep}"]  = tonumber(usep)
         end
     end
     f:close()

gmail.lua

@@ -4,6 +4,7 @@
 ---------------------------------------------------
 
 -- {{{ Grab environment
+local tonumber = tonumber
 local io = { popen = io.popen }
 local setmetatable = setmetatable
 local string = { match = string.match }
@@ -24,7 +25,7 @@ local function worker(format, feed)
     local auth = user .. ":" .. pass
     local feed = feed or "https://mail.google.com/mail/feed/atom/unread"
     local mail = {
-        ["{count}"]   = "0",
+        ["{count}"]   = 0,
         ["{subject}"] = "N/A"
     }
 
@@ -34,7 +35,7 @@ local function worker(format, feed)
     -- Could be huge don't read it all at once, info we are after is at the top
     for line in f:lines() do
         mail["{count}"] = -- Count comes before messages and matches at least 0
-          string.match(line, "<fullcount>([%d]+)</fullcount>") or mail["{count}"]
+          tonumber(string.match(line, "<fullcount>([%d]+)</fullcount>")) or mail["{count}"]
 
         -- Find subject tags
         local title = string.match(line, "<title>(.*)</title>")

hddtemp.lua

@@ -4,6 +4,7 @@
 ---------------------------------------------------
 
 -- {{{ Grab environment
+local tonumber = tonumber
 local io = { popen = io.popen }
 local setmetatable = setmetatable
 local string = { match = string.match }
@@ -27,7 +28,7 @@ local function worker(format, port)
         local disk, temp = string.match(line, "|([%/%a]+)|.*|([%d]+)|[CF]+|")
 
         if disk ~= nil and temp ~= nil then
-            hdd_temp["{"..disk.."}"] = temp
+            hdd_temp["{"..disk.."}"] = tonumber(temp)
         end
     end
     f:close()

load.lua

@@ -4,6 +4,7 @@
 ---------------------------------------------------
 
 -- {{{ Grab environment
+local tonumber = tonumber
 local io = { open = io.open }
 local setmetatable = setmetatable
 local string = { match = string.match }
@@ -23,7 +24,7 @@ local function worker(format)
     local l1, l5, l15 =  -- Get load averages for past 1, 5 and 15 minutes
       string.match(line, "([%d]*%.[%d]*)%s([%d]*%.[%d]*)%s([%d]*%.[%d]*)")
 
-    return {l1, l5, l15}
+    return {tonumber(l1), tonumber(l5), tonumber(l15)}
 end
 -- }}}
 

thermal.lua

@@ -4,6 +4,7 @@
 ---------------------------------------------------
 
 -- {{{ Grab environment
+local tonumber = tonumber
 local io = { open = io.open }
 local setmetatable = setmetatable
 local string = { match = string.match }
@@ -19,11 +20,11 @@ local function worker(format, thermal_zone)
     -- Get an ACPI thermal zone
     local f = io.open("/proc/acpi/thermal_zone/"..thermal_zone.."/temperature")
     -- Handler for incompetent users
-    if not f then return {"N/A"} end
+    if not f then return {0} end
     local line = f:read("*line")
     f:close()
 
-    local temperature = string.match(line, "[%d]?[%d]?[%d]")
+    local temperature = tonumber(string.match(line, "[%d]?[%d]?[%d]"))
 
     return {temperature}
 end

volume.lua

@@ -4,6 +4,7 @@
 ---------------------------------------------------
 
 -- {{{ Grab environment
+local tonumber = tonumber
 local io = { popen = io.popen }
 local setmetatable = setmetatable
 local string = {
@@ -24,8 +25,8 @@ local function worker(format, channel)
     local mixer = f:read("*all")
     f:close()
 
-    local vol = string.match(mixer, "([%d]?[%d]?[%d])%%")
-    -- If muted return 0 (not "Mute") so we dont break progressbars
+    local vol = tonumber(string.match(mixer, "([%d]?[%d]?[%d])%%"))
+    -- If mute return 0 (not "Mute") so we don't break progressbars
     if string.find(mixer, "%[off%]") or vol == nil then
         vol = 0
     end

wifi.lua

@@ -4,6 +4,7 @@
 ---------------------------------------------------
 
 -- {{{ Grab environment
+local tonumber = tonumber
 local io = { popen = io.popen }
 local setmetatable = setmetatable
 local string = {
@@ -30,7 +31,7 @@ local function worker(format, iface)
         ["{mode}"] = "N/A",
         ["{chan}"] = "N/A",
         ["{rate}"] = "N/A",
-        ["{link}"] = "N/A",
+        ["{link}"] = 0,
         ["{sign}"] = "N/A"
     }
 
@@ -47,13 +48,13 @@ local function worker(format, iface)
     winfo["{mode}"] =  -- Modes are simple, but also match the "-" in Ad-Hoc
       string.match(iw, "Mode[=:]([%w%-]*)") or winfo["{mode}"]
     winfo["{chan}"] =  -- Channels are plain digits
-      string.match(iw, "Channel[=:]([%d]+)") or winfo["{chan}"]
+      tonumber(string.match(iw, "Channel[=:]([%d]+)") or winfo["{chan}"])
     winfo["{rate}"] =  -- Bitrate can start with a space and we want to display Mb/s
       string.match(iw, "Bit Rate[=:]([%s]?[%d%.]*[%s][%/%a]+)") or winfo["{rate}"]
 --  winfo["{link}"] =  -- Link quality can contain a slash: 32/100
 --    string.match(iw, "Link Quality[=:]([%d]+[%/%d]*)") or winfo["{link}"]
-    winfo["{link}"] =  --  * match only the first number, great data for a progressbar
-      string.match(iw, "Link Quality[=:]([%d]+)") or winfo["{link}"]
+    winfo["{link}"] =  --  * match only the first number, also suitable for a progressbar
+      tonumber(string.match(iw, "Link Quality[=:]([%d]+)") or winfo["{link}"])
     winfo["{sign}"] =  -- Signal level can be a negative value, also display decibel notation
       string.match(iw, "Signal level[=:]([%-%d]+[%s][%a]*)") or winfo["{sign}"]