Looks like the simplest acceptable (if not always correct) compromise would be:
local decimal = string.match(string.format("%.1f",1/5),"([^0-9])") local thousands = "\226\128\137"The WoW client allows decimal escaped Unicode sequences:
U+2009 "THIN SPACE" ==> \226\128\137
Of course, this is probably dependent on what fonts are available at the time :-\
edit: clarification - none of the four base WoW client fonts have large character sets and even if there's no visible glyph, it would still have to be defined. Windows and Mac (and I assume Linux) have systems in place to borrow characters from other fonts to fill out Unicode ranges, but I have no idea whether the WoW client hooks into this system or not ... test first :-)
edit: addendum - tried it out and the "thin space" is a no-go :-\ (the escape sequence above prints a zero-width question mark)
On the other hand, most people playing with UIs are running their fonts at such small sizes that a normal space would probably work just as well, legibility wise ...