Tables | Lua by Example

Basic manipulation

Tables are the only data structure available in Lua that helps us create different types like arrays and dictionaries.

local colors = { "red", "green", "blue" }

print(colors[1])
print(colors[2])
print(colors[3])

io.write("Number of Items : ", #colors, "\n")

red
green
blue
Number of Items : 3

Range over table

Note that numeration starts with 1 - not 0 like in most languages. To iterate though table:

for i=1, #colors do
  print(colors[i])
end

red
green
blue

local colors = { "red", "green", "blue" }

for k, v in pairs(colors) do
  io.write(k, ":", v, "\n")
end

1:red
2:green
3:blue

Append to the end of the table

local colors = { "red", "green", "blue" }

table.insert(colors, "orange")
local index = #colors --4 (this is the last index in the table)
print(colors[index])

orange

Insert at index

local colors = { "red", "green", "blue" }
table.insert(colors, 2, "pink")
for i=1, #colors do
  print(colors[i])
end

red
pink
green
blue

Remove

local colors = { "red", "green", "blue" }
table.remove(colors, 1)
for i=1, #colors do
  print(colors[i])
end

green
blue