44 lines
652 B
Markdown
44 lines
652 B
Markdown
# Lists
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Lists are a standard Ava type. Specifically, `List[A]` represents a linked list.
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```
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let x: List[Int32] := { 1, 2, 3 }
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let y := prepend(x, 0)
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let z := append(x, { 4, 5 })
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let w: Option[Int32] := head(x)
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let tail: List[Int32] := tail(x)
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let sz: List[Int32] := size(x)
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```
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## Type Class Support
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- `Monad`
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- `Monoid`
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- `Show`
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- `Eq`
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## NonEmptyList
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The type `NonEmptyList` is a list which cannot be empty:
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```
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given A
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record NonEmptyList: (head: A, tail: List[A])
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```
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## Indexing
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Lists cannot be accessed by index.
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## Implementation
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```
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given A
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enum List
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object Nil
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given A
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record List(head: A, tail: List[A])
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end enum
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```
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