update

helpers.rb

@@ -0,0 +1,20 @@
+def thousands(n, sep = ',')
+  s = n.to_s
+  sign = s[0] == '-' ? '-' : ''
+  s = s[1..-1] if sign == '-'
+
+  int, frac = s.split('.', 2)
+
+  out = ''
+  count = 0
+
+  int.reverse.each_char do |c|
+    out << sep if count > 0 && count % 3 == 0
+    out << c
+    count += 1
+  end
+
+  int = out.reverse
+
+  frac ? "#{sign}#{int}.#{frac}" : "#{sign}#{int}"
+end

lua_init.lua

@@ -0,0 +1,16 @@
+local function escape_pattern(s)
+	return (s:gsub("(%W)", "%%%1"))
+end
+
+function Thousands(n, sep)
+	sep = sep or "."
+	local s = tostring(n)
+	local sign, int, frac = s:match("^([%-]?)(%d+)(%.?%d*)$")
+
+	int = int:reverse():gsub("(%d%d%d)", "%1" .. sep):reverse()
+
+	local sep_esc = escape_pattern(sep)
+	int = int:gsub("^" .. sep_esc, "")
+
+	return sign .. int .. frac
+end