startledhippo
Pattern match first element of list value in a map
Hi,
Given
test = %{a: 1, b: [%{c: 1,d: 2}] }
How do I pattern match to get values c and d? I tried the following:
%{a: a, [%{c: value1, d: value2} | _ ] = b} = test
but it gives me:
** (SyntaxError) iex:9: syntax error before: ‘[’
Is there a way to pattern match the nested values in the list?
Thanks for the help!
Marked As Solved
cpgo
You have a few syntax errors.
test = %{a: 1, b: [%{c: 1, d: 2}, %{c: 3, d: 4}, %{c: 5, d: 6}, %{c: 7, d: 8}] }
%{a: a, b: [%{c: value1, d: value2} | rest ] } = test
IO.inspect a
IO.inspect value1
IO.inspect value2
IO.inspect rest
1
1
2
[%{c: 3, d: 4}, %{c: 5, d: 6}, %{c: 7, d: 8}]
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