how to use tables in lua code example

Example 1: lua list of all keys

-- This is a list of how to write all the keys in Lua:
https://github.com/me2d13/luamacros/wiki/List-of-Keys

Example 2: table lua

a = {}
    x = "y"
    a[x] = 10                 -- put 10 in field "y"
    print(a[x])   --> 10      -- value of field "y"
    print(a.x)    --> nil     -- value of field "x" (undefined)
    print(a.y)    --> 10      -- value of field "y"