lib: lists: add countValues
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@ -1,8 +1,22 @@
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{ lib, ... }:
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{ lib, ... }:
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let
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let
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inherit (lib) filter;
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inherit (lib) filter foldl';
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in
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in
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{
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{
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# Count the number of appararitions of each value in a list.
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#
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# countValues ::
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# [ any ] -> ({ any = int; })
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countValues =
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let
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addToCount = acc: x:
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let
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v = toString x;
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in
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acc // { ${v} = (acc.${v} or 0) + 1; };
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in
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foldl' addToCount { };
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# Filter a list using a predicate function after applying a map.
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# Filter a list using a predicate function after applying a map.
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#
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#
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# mapFilter ::
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# mapFilter ::
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