pairs and ipairs in Lua

ipairs walks the array part in order; pairs walks every key.

-- ipairs walks the array part in order; pairs walks every key.
local loot = { "coin", "coin", "idol" }
for i, item in ipairs(loot) do
  print(i .. ". " .. item)
end

local prices = { idol = 300, coin = 1, lantern = 12 }
local total_kinds = 0
for item, price in pairs(prices) do
  total_kinds = total_kinds + 1
  print(string.format("%s sells for %d", item, price))
end
print(total_kinds .. " kinds appraised")

How it works

ipairs stops at the first nil hole.
pairs visits string keys too, in no promised order.
Both drive the same generic for k, v in shape.

Keywords and builtins used here

do
end
for
in
ipairs
local
pairs
print

The run, in numbers

Lines: 13
Characters to type: 404
Tokens: 94
Three-star pace: 65 tpm

At the three-star pace of 65 tokens a minute, this run takes about 87 seconds.

Type this snippet

Step 3 of 4 in Tables, step 9 of 27 in Language basics.

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