Converts the Lua value at the given acceptable index to the signed
integral type
Integer. The Lua value must be an integer, a
number or a string convertible to an integer (see
§3.4.3 of the
Lua 5.4 Reference Manual); otherwise,
tointeger returns
Nothing.
If the number is not an integer, it is truncated in some non-specified
way.
Wraps
lua_tointegerx. See also:
lua_tointeger.