Global variables via _G

Other Standard Library features. example from a Well House Consultants training course
More on Other Standard Library features. [link]

Source code: globals Module: U112

--[[
In Lua, Global variables are accessible via the _G
table ...
]]

function tellme()
        for n,v in pairs(_G) do
                print (n,v)
                end
        end

starter = "Prawn Cocktail"
main = "Jellied Eel"
desert = "Pineapple"

tellme()

--[[ Example output
[trainee@easterton u112]$ lua globals
string table: 0x9a615b8
xpcall function: 0x9a60fb0
package table: 0x9a61a50
tostring function: 0x9a60f08
print function: 0x9a61020
os table: 0x9a63230
unpack function: 0x9a60f78
require function: 0x9a61fc8
getfenv function: 0x9a60c48
setmetatable function: 0x9a60e90
next function: 0x9a60d68
assert function: 0x9a60b98
tonumber function: 0x9a60ed0
io table: 0x9a62a28
rawequal function: 0x9a61058
collectgarbage function: 0x9a60bd0
arg table: 0x9a64d60
getmetatable function: 0x9a60de0
module function: 0x9a61d20
rawset function: 0x9a610c8
desert Pineapple
_VERSION Lua 5.1
debug table: 0x9a64810
ipairs function: 0x9a609a0
math table: 0x9a63e10
starter Prawn Cocktail
pcall function: 0x9a60da0
table table: 0x9a61828
newproxy function: 0x9a616b0
type function: 0x9a60f40
coroutine table: 0x9a61718
_G table: 0x9a60450
select function: 0x9a60478
gcinfo function: 0x9a60c10
pairs function: 0x9a60a00
rawget function: 0x9a61090
loadstring function: 0x9a60d30
tellme function: 0x9a65260
main Jellied Eel
dofile function: 0x9a60c88
setfenv function: 0x9a60e58
load function: 0x9a60cf8
error function: 0x9a60cc0
loadfile function: 0x9a60e20
[trainee@easterton u112]$
]]

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