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Erlang / Erlang Basics Interview questions

How do you handle errors in Erlang without try/catch?

Erlang's idiomatic style leans on tagged return values for expected, recoverable failure conditions, reserving exceptions (and try/catch) for genuinely unexpected situations. A function that can fail in an "ordinary" way typically returns {ok, Value} or {error, Reason}, and the caller pattern-matches on the outcome.

case file:read_file("config.txt") of
    {ok, Data} -> process(Data);
    {error, Reason} -> log_error(Reason)
end.

This keeps the "unhappy path" visible in the type of the return value rather than hidden in a control-flow jump, and it composes naturally with pattern matching in function clauses. Genuinely exceptional, programmer-error-style failures (a failed match, a bad arithmetic operation) are left to crash the process and get handled by a supervisor instead — which is the "let it crash" side of Erlang's error strategy.

What is the idiomatic way to signal an expected, recoverable failure in Erlang?
What category of failure is generally left to crash the process instead of being caught?

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