23 lines
550 B
Nix
23 lines
550 B
Nix
{ lib }:
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let
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chrs = lib.listToAttrs (
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lib.imap (i: v: {
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name = v;
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value = i + 96;
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}) lib.lowerChars
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);
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ord = c: builtins.getAttr c chrs;
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in
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{
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# Make a unique UID from a 4-char identifier
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mkUid =
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id:
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let
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chars = lib.stringToCharacters (builtins.substring 0 4 id);
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n = builtins.map (c: lib.mod (ord c) 10) chars;
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s = builtins.concatStringsSep "" (builtins.map builtins.toString n);
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in
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assert builtins.stringLength id >= 4;
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assert builtins.length chars == 4;
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1000 + lib.toInt s;
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}
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