46 lines
736 B
Nix
46 lines
736 B
Nix
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{lib}: rec {
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/*
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Base raised to the power of the exponent.
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Type: pow :: int or float -> int -> int
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Args:
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base: The base.
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exponent: The exponent.
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Example:
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pow 0 1000
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=> 0
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pow 1000 0
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=> 1
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pow 2 30
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=> 1073741824
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pow 3 3
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=> 27
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pow (-5) 3
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=> -125
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*/
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pow = base: exponent: let
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inherit (lib) mod;
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in
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if exponent > 1
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then let
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x = pow base (exponent / 2);
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odd_exp = mod exponent 2 == 1;
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in
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x
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* x
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* (
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if odd_exp
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then base
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else 1
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)
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else if exponent == 1
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then base
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else if exponent == 0 && base == 0
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then throw "undefined"
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else if exponent == 0
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then 1
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else throw "undefined";
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}
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