d315210612
With this primitive, a list-flattening function can be implemented (NIX-55, example is in tests/lang/eval-okay-flatten.nix).
20 lines
349 B
Nix
20 lines
349 B
Nix
let {
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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:
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if builtins.isList x
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then fold (x: y: (flatten x) ++ y) [] x
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else [x];
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l = ["1" "2" ["3" ["4"] ["5" "6"]] "7"];
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body = concat (flatten l);
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}
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