40 lines
1 KiB
Nix
40 lines
1 KiB
Nix
rec {
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# Identity function.
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id = x: x;
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# Constant function.
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const = x: y: x;
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# Named versions corresponding to some builtin operators.
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concat = x: y: x ++ y;
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or = x: y: x || y;
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and = x: y: x && y;
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mergeAttrs = x: y: x // y;
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# Take a function and evaluate it with its own returned value.
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fix = f: let result = f result; in result;
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# Flip the order of the arguments of a binary function.
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flip = f: a: b: f b a;
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# Pull in some builtins not included elsewhere.
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inherit (builtins)
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pathExists readFile isBool isFunction
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isInt add sub lessThan
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seq deepSeq genericClosure;
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# Return the Nixpkgs version number.
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nixpkgsVersion =
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let suffixFile = ../.version-suffix; in
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readFile ../.version
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+ (if pathExists suffixFile then readFile suffixFile else "pre-git");
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# Whether we're being called by nix-shell.
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inNixShell = builtins.getEnv "IN_NIX_SHELL" == "1";
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# Return minimum/maximum of two numbers.
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min = x: y: if x < y then x else y;
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max = x: y: if x > y then x else y;
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}
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