61 lines
1.2 KiB
Markdown
61 lines
1.2 KiB
Markdown
# Tuples
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Tuples are heterogeneous, fixed-size, collections of values. Tuples contain 0 to
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`N` values, where `N` is unbounded. Tuples are similar to [Records](records.md),
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but records have named parameters.
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## Syntax
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```
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let x := ()
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let y := ("foo")
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let z := ("foo", 1)
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let w := ("foo", 1, true, 3.14)
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```
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## Type of a Standard Tuple
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Consider the tuple `("foo", 1, true, 3.14)`. It has type
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`(String, Int32, Boolean, Float64)`.
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## The Empty Tuple
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The type `()` has a single possible value, `()`. This is the empty tuple. It is
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typically used as a token to indicate side-effects with no other useful output.
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## Accessing Tuple Members
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Each tuple member is _indexed_ and can be directly accessed via a property of
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that index:
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```
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let w := ("foo", 1, true)
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let x := w._1
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let y := w._2
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let z := w._3
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```
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## Destructuring Tuples
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Tuples can be _destructured_ via [pattern matching](pattern-matching.md)
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capabilities. This can take two possible forms.
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### Destructured Binding
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Tuples may be destructured at the point of binding.
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```
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let w := ("foo", 1, true)
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let (x, y, z) := w
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```
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### Destructured Match Case
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```
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let w := ("foo", 1, true)
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let z :=
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match w
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case ("foo", _, x) => x
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case _ => false
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```
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