tushar
Pattern matching in multi level nested maps
How do I pattern match in multi-level nested maps
Suppose this is my map ,
mymap = %{a: "xxx" , b: %{k1: "k1" , k2: "k2" , c: %{k3: "k3", k4: "k4"}}}
When I do this , I get an error ,
** %{a: v1, b: %{k1: v2, k2: v3, c: %{k3: v4, k4: v4}}} = mymap **
** (MatchError) no match of right hand side value: %{a: "xxx", b: %{c: %{k3: "k3", k4: "k4"}, k1: "k1", k2: "k2"}}
(stdlib) erl_eval.erl:453: :erl_eval.expr/5
(iex) lib/iex/evaluator.ex:257: IEx.Evaluator.handle_eval/5
(iex) lib/iex/evaluator.ex:237: IEx.Evaluator.do_eval/3
(iex) lib/iex/evaluator.ex:215: IEx.Evaluator.eval/3
(iex) lib/iex/evaluator.ex:103: IEx.Evaluator.loop/1
(iex) lib/iex/evaluator.ex:27: IEx.Evaluator.init/4
Marked As Solved
NobbZ
You ask here that :k3 and :k4 have values that meatch.
2
Also Liked
mentero
you still didn’t fix the typo. You ask that k3: and k4: both have the same value v4 but then pass "k3" and "k4 as the values. Your pattern is OK, your data simply doesn’t match.
1
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