lua: add a function that formats Lua values as strings

Yep, Lua is so crappy that the stdlib doesn't provide anything like
this.

Repurposes the undocumented mp.format_table() function and moves it to
mp.utils.

1 files changed, 2 insertions, 8 deletions

diff --git a/TOOLS/lua/observe-all.lua b/TOOLS/lua/observe-all.lua
index 68e09773c6..9bfdf44992 100644
--- a/TOOLS/lua/observe-all.lua
+++ b/TOOLS/lua/observe-all.lua
@@ -1,16 +1,10 @@
 -- Test script for property change notification mechanism.
 
-function format_property_val(v)
-    if type(v) == "table" then
-        return mp.format_table(v) -- undocumented function; might be removed
-    else
-        return tostring(v)
-    end
-end
+local utils = require("mp.utils")
 
 for i,name in ipairs(mp.get_property_native("property-list")) do
     mp.observe_property(name, "native", function(name, val)
         print("property '" .. name .. "' changed to '" ..
-              format_property_val(val) .. "'")
+              utils.to_string(val) .. "'")
     end)
 end