Lua 5.3 standard library for UTF-8 manipulation
$ luarocks install --server=https://luarocks.org/dev lutf8
Lua 5.3 came with a nice UTF-8 support library internally boundled.
This is that same library packaged as a standalone library, which can be used by any version of Lua (5.1, 5.2 and LuaJIT).
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