monoid.nix

with rec {
  function = import ./function.nix;
  inherit (function) compose id flip;

  semigroup = import ./semigroup.nix;

  imports = {
    list = import ./list.nix;
    string = import ./string.nix;
    nullable = import ./nullable.nix;
    optional = import ./optional.nix;
  };
};

rec {
  first = optional semigroup.first;

  last = optional semigroup.last;

  min = optional semigroup.min;

  max = optional semigroup.max;

  dual = monoid: semigroup.dual monoid // {
    empty = monoid.empty;
  };

  endo = semigroup.endo // {
    empty = id;
  };

  all = semigroup.all // {
    empty = true;
  };

  and = semigroup.and // {
    empty = false;
  };

  list = imports.list.monoid;

  string = imports.string.monoid;

  nullable = imports.nullable.monoid;

  optional = imports.optional.monoid;
}