Need help with a Custom empty? function

I have this sample data structure below.

It is considered not empty if any of it’s Decimal values is greater than decimal<0>

Please how would you check for that?

My code below incorrectly returns false, when it should return true:

  def empty?(data) do
    if Enum.empty?(data) do
      true
    else
      Enum.any?(data, fn x ->
        Decimal.decimal?(x) && !(Decimal.cmp(x, Decimal.new(0)) == :eq)
      end)
    end
  end

data = %{"10100" => [{{1, 1, "employer-issuer-code"}, "PEC000000000000"}, {{1, 2, "instrument-code"}, "OTH20000000"}, {{1, 3, "instrument-rating"}, "00"}, {{1, 4, "coupon-rate"}, #Decimal<0.00>}, {{1, 5, "foreign-currency-type"}, "EUR"}, {{1, 6, "conversion-rate"}, #Decimal<0.0000>}, {{1, 7, "issue-amount-foreign-currency"}, #Decimal<0.00>}, {{1, 8, "face-value-foreign-currency"}, #Decimal<0.00>}, {{1, 9, "holding-units"}, #Decimal<0.0000>}, {{1, 10, "cost-foreign-currency"}, #Decimal<0.00>}, {{1, 11, "value-date"}, "31-Mar-2017"}, {{1, 12, "maturity-date"}, "31-Mar-2017"}, {{1, 13, "accrued-coupon-to-date-foreign-currency"}, #Decimal<0.00>}, {{1, 14, "market-value-foreign-currency"}, #Decimal<0.00>}, {{1, 15, "market-value-naira"}, #Decimal<0.00>}], "20100" => [{{1, 1, "employer-issuer-code"}, "PEC000000000000"}, {{1, 2, "instrument-code"}, "OTH20000000"}, {{1, 3, "instrument-rating"}, "00"}, {{1, 4, "coupon-rate"}, #Decimal<0.00>}, {{1, 5, "foreign-currency-type"}, "EUR"}, {{1, 6, "conversion-rate"}, #Decimal<0.0000>}, {{1, 7, "issue-amount-foreign-currency"}, #Decimal<0.00>}, {{1, 8, "face-value-foreign-currency"}, #Decimal<0.00>}, {{1, 9, "holding-units"}, #Decimal<0.0000>}, {{1, 10, "cost-foreign-currency"}, #Decimal<0.00>}, {{1, 11, "value-date"}, "31-Mar-2017"}, {{1, 12, "maturity-date"}, "31-Mar-2017"}, {{1, 13, "accrued-coupon-to-date-foreign-currency"}, #Decimal<0.00>}, {{1, 14, "market-value-foreign-currency"}, #Decimal<0.00>}, {{1, 15, "market-value-naira"}, #Decimal<0.00>}], "30100" => [{{1, 1, "employer-issuer-code"}, "PEC000000000000"}, {{1, 2, "instrument-code"}, "OTH20000000"}, {{1, 3, "instrument-rating"}, "00"}, {{1, 4, "coupon-rate"}, #Decimal<0.00>}, {{1, 5, "foreign-currency-type"}, "EUR"}, {{1, 6, "conversion-rate"}, #Decimal<0.0000>}, {{1, 7, "issue-amount-foreign-currency"}, #Decimal<0.00>}, {{1, 8, "face-value-foreign-currency"}, #Decimal<0.00>}, {{1, 9, "holding-units"}, #Decimal<0.0000>}, {{1, 10, "cost-foreign-currency"}, #Decimal<0.00>}, {{1, 11, "value-date"}, "31-Mar-2017"}, {{1, 12, "maturity-date"}, "31-Mar-2017"}, {{1, 13, "accrued-coupon-to-date-foreign-currency"}, #Decimal<0.00>}, {{1, 14, "market-value-foreign-currency"}, #Decimal<0.00>}, {{1, 15, "market-value-naira"}, #Decimal<0.00>}], "40104" => [{{1, 1, "employer-issuer-code"}, "PEC000000000000"}, {{1, 2, "instrument-code"}, "OTH20000000"}, {{1, 3, "instrument-rating"}, "00"}, {{1, 4, "coupon-rate"}, #Decimal<0.00>}, {{1, 5, "foreign-currency-type"}, "EUR"}, {{1, 6, "conversion-rate"}, #Decimal<0.0000>}, {{1, 7, "issue-amount-foreign-currency"}, #Decimal<0.00>}, {{1, 8, "face-value-foreign-currency"}, #Decimal<0.00>}, {{1, 9, "holding-units"}, #Decimal<0.0000>}, {{1, 10, "cost-foreign-currency"}, #Decimal<0.00>}, {{1, 11, "value-date"}, "31-Mar-2017"}, {{1, 12, "maturity-date"}, "31-Mar-2017"}, {{1, 13, "accrued-coupon-to-date-foreign-currency"}, #Decimal<0.00>}, {{1, 14, "market-value-foreign-currency"}, #Decimal<0.00>}, {{1, 15, "market-value-naira"}, #Decimal<0.00>}], "40153" => [{{1, 1, "employer-issuer-code"}, "PEC000000000000"}, {{1, 2, "instrument-code"}, "OTH20000000"}, {{1, 3, "instrument-rating"}, "00"}, {{1, 4, "coupon-rate"}, #Decimal<0.00>}, {{1, 5, "foreign-currency-type"}, "EUR"}, {{1, 6, "conversion-rate"}, #Decimal<0.0000>}, {{1, 7, "issue-amount-foreign-currency"}, #Decimal<0.00>}, {{1, 8, "face-value-foreign-currency"}, #Decimal<0.00>}, {{1, 9, "holding-units"}, #Decimal<0.0000>}, {{1, 10, "cost-foreign-currency"}, #Decimal<0.00>}, {{1, 11, "value-date"}, "31-Mar-2017"}, {{1, 12, "maturity-date"}, "31-Mar-2017"}, {{1, 13, "accrued-coupon-to-date-foreign-currency"}, #Decimal<0.00>}, {{1, 14, "market-value-foreign-currency"}, #Decimal<0.00>}, {{1, 15, "market-value-naira"}, #Decimal<0.00>}], "40191" => [{{1, 1, "employer-issuer-code"}, "PEC000000000000"}, {{1, 2, "instrument-code"}, "OTH20000000"}, {{1, 3, "instrument-rating"}, "00"}, {{1, 4, "coupon-rate"}, #Decimal<0.00>}, {{1, 5, "foreign-currency-type"}, "EUR"}, {{1, 6, "conversion-rate"}, #Decimal<0.0000>}, {{1, 7, "issue-amount-foreign-currency"}, #Decimal<0.00>}, {{1, 8, "face-value-foreign-currency"}, #Decimal<0.00>}, {{1, 9, "holding-units"}, #Decimal<0.0000>}, {{1, 10, "cost-foreign-currency"}, #Decimal<0.00>}, {{1, 11, "value-date"}, "31-Mar-2017"}, {{1, 12, "maturity-date"}, "31-Mar-2017"}, {{1, 13, "accrued-coupon-to-date-foreign-currency"}, #Decimal<0.00>}, {{1, 14, "market-value-foreign-currency"}, #Decimal<0.00>}, {{1, 15, "market-value-naira"}, #Decimal<0.00>}], "40192" => [{{1, 1, "employer-issuer-code"}, "PEC000000000000"}, {{1, 2, "instrument-code"}, "OTH20000000"}, {{1, 3, "instrument-rating"}, "00"}, {{1, 4, "coupon-rate"}, #Decimal<0.00>}, {{1, 5, "foreign-currency-type"}, "EUR"}, {{1, 6, "conversion-rate"}, #Decimal<0.0000>}, {{1, 7, "issue-amount-foreign-currency"}, #Decimal<0.00>}, {{1, 8, "face-value-foreign-currency"}, #Decimal<0.00>}, {{1, 9, "holding-units"}, #Decimal<0.0000>}, {{1, 10, "cost-foreign-currency"}, #Decimal<0.00>}, {{1, 11, "value-date"}, "31-Mar-2017"}, {{1, 12, "maturity-date"}, "31-Mar-2017"}, {{1, 13, "accrued-coupon-to-date-foreign-currency"}, #Decimal<0.00>}, {{1, 14, "market-value-foreign-currency"}, #Decimal<0.00>}, {{1, 15, "market-value-naira"}, #Decimal<0.00>}], "70100" => [{{1, 1, "employer-issuer-code"}, "PEC000000000000"}, {{1, 2, "instrument-code"}, "OTH20000000"}, {{1, 3, "instrument-rating"}, "00"}, {{1, 4, "coupon-rate"}, #Decimal<0.00>}, {{1, 5, "foreign-currency-type"}, "EUR"}, {{1, 6, "conversion-rate"}, #Decimal<0.0000>}, {{1, 7, "issue-amount-foreign-currency"}, #Decimal<0.00>}, {{1, 8, "face-value-foreign-currency"}, #Decimal<0.00>}, {{1, 9, "holding-units"}, #Decimal<0.0000>}, {{1, 10, "cost-foreign-currency"}, #Decimal<0.00>}, {{1, 11, "value-date"}, "31-Mar-2017"}, {{1, 12, "maturity-date"}, "31-Mar-2017"}, {{1, 13, "accrued-coupon-to-date-foreign-currency"}, #Decimal<0.00>}, {{1, 14, "market-value-foreign-currency"}, #Decimal<0.00>}, {{1, 15, "market-value-naira"}, #Decimal<0.00>}]}

Please don’t paste huge iex dumps. Just explain your problem and requirements.

Quick prototype:

defmodule Something do
  def decimal_zero(), do: Decimal.new(0.0)

  def empty?(nil), do: true

  def empty?(%Decimal{} = d) do
    Decimal.cmp(d, decimal_zero()) == :eq  
  end

  def empty?(list) when is_list(list) do
    Enum.any?(list, &(not empty?(&1))
  end
end

You can extend this to tuples and maps if you need support for those.

Thanks. This might not work. The structure I have is quite deep.

You were given a good start. You can do the rest easily.

There are ways of saying this that sound less hostile.

What would you propose? I was a bit sharp, but hostile… hm.

I’ll accept sharp in lieu of hostile.

“What I wrote should cover the fundamental idea, see if you can extend it further on your own, and post back here if you run into issues.”

Point taken for the future. Thank you.