49 lines
1.0 KiB
Plaintext
49 lines
1.0 KiB
Plaintext
import option
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import super::fn::*
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pair := \a.\b. \f. f a b
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-- Constructors
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export cons := \hd.\tl. option::some (pair hd tl)
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export end := option::none
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export pop := \list.\default.\f.list default \cons.cons f
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-- Operators
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export reduce := \list.\acc.\f. (
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loop r on (list acc) with
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pop list acc \head.\tail. r tail (f acc head)
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)
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export map := \list.\f. (
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loop r on (list) with
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pop list end \head.\tail. cons (f head) (r tail)
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)
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export skip := \list.\n. (
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loop r on (list n) with
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if n == 0 then list
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else pop list end \head.\tail. r tail (n - 1)
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)
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export take := \list.\n. (
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loop r on (list n) with
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if n == 0 then end
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else pop list end \head.\tail. cons head $ r tail $ n - 1
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)
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export get := \list.\n. (
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loop r on (list n) with
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pop list option::none \head.\tail.
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if n == 0 then option::some head
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else r tail (n - 1)
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)
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new[...$item, ...$rest:1] =0x2p84=> (cons (...$item) new[...$rest])
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new[...$end] =0x1p84=> (cons (...$end) end)
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new[] =0x1p84=> end
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export ::(new)
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