fix sprintf and rename to fmt

the "split on %" strategy makes parsing "%%" complicated, so the "actually literally %" placeholder is now "%~" rather than "%%". since thsi resembles a real sprintf even less now I renamed it to "fmt".

also actually closes the `if m == "~"` block. (which was `if m == "%"` before this patch)

chameleonic.p8

@@ -39,14 +39,13 @@ function cycle(tbl,period)
 end
 
 -- fake sprintf function
--- %% for literal "%"
+-- %~ for literal "%"
 -- %v for param
-
-function sprintf(fmt, ...)
+function fmt(f, ...)
  local out, i = "", 1
- for s in all(split(fmt,"%")) do
+ for s in all(split(f,"%")) do
   local m = s[1]
-  if m == "%" then
+  if m == "~" then
    out ..= "%"
   else
    local p = select(i,...)
@@ -56,6 +55,7 @@ function sprintf(fmt, ...)
    else
     out ..= "(?!:"..m..":"..tostr(p)..")"
    end
+  end
   out ..=sub(s,2)
  end
  return out