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rec {
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fold = op: nul: list:
|
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if list == []
|
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then nul
|
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else op (builtins.head list) (fold op nul (builtins.tail list));
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concat =
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fold (x: y: x + y) "";
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flatten = x:
|
|
if builtins.isList x
|
|
then fold (x: y: (flatten x) ++ y) [] x
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else [x];
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|
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sum = fold (x: y: builtins.add x y) 0;
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|
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}
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