KC3 tuples are immutable arrays of Tag. They contain a fixed number of
constant values of any type. Tuple access is very fast.
Tuples can be used to return more than one value from a function.
For example a successful function call might result in a
{:ok, result} tuple, while an error might produce the
{:error, "Message", data, trace} tuple.
ikc3> a = {:ok, "My title", "Hello, world !"}
{:ok, "My title", "Hello, world !"}
Destructuring works with tuples to extract values :
ikc3> {:ok, title, message} = ^ a
{:ok, "My title", "Hello, world !"}
ikc3> title
"My title"
ikc3> message
"Hello, world !"
The bracket syntax allows you to query the tag at a tuple position :
ikc3> a[0]
:ok
ikc3> a[1]
"My title"
ikc3> a[2]
"Hello, world !"
You can also use the KC3.access function for the same result :
ikc3> a = {:ok, "My title", "Hello, world !"}
{:ok, "My title", "Hello, world !"}
ikc3> access(a, [0])
:ok
ikc3> access(a, [1])
"My title"
ikc3> access(a, [2])
"Hello, world !"