benonymus
How to check if the params has a parameter but it is nil or it is not there at all?
basically the title, I would need to check the params and do different things depending on whether there is a parameter with a value, is that value nil or not, or the parameter is not there at all.
Is this possible?
Thank you
Marked As Solved
benwilson512
Author of Craft GraphQL APIs in Elixir with Absinthe
case Map.fetch(params, key) do
{:ok, nil} -> # it's here and it's nil
{:ok, value} -> # it's here and it's not nil
:error -> # it isn't present
end
7
Also Liked
NobbZ
case params do
%{"foo" => nil} -> # it is nil
%{"foo" => val} -> # it is there and has a value
%{} -> # it is not there
end
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