Questions & Help>Questions

Get field names of a struct

#structs
alexcastano

alexcastano

Get field names of a struct

Hello,

Is there a way to get the list of fields with only the struct module?

iex> something(Date)
[:calendar, :year, :day, :month]

I tried this, but it doesn’t work if @enforce_keys are defined:

iex(4)> Map.keys(%Date{})
** (ArgumentError) the following keys must also be given when building struct Date: [:year, :month, :day]
    (elixir) expanding struct: Date.__struct__/1
    iex:4: (file)

At first glance it does not seem that any function is created for this either:

3 comments
#structs
8 5852 3

Marked As Solved

LostKobrakai

LostKobrakai

This seems to work:

iex(2)> Date.__struct__() |> Map.keys()
[:__struct__, :calendar, :day, :month, :year]
5
Post #2

Also Liked

krisleech

krisleech

This seems to work for any struct:

struct(Foo, %{}) |> Map.from_struct() |> Map.keys()

2
Post #3

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