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Elixir / Errors and Control

Custom exceptions

Learn Custom exceptions in Elixir through a focused explanation, a dedicated topic-specific example, an engineering boundary, and a mastery check.

12 min read • Intermediate

Custom exceptions is a focused Elixir lesson inside Errors and Control. The example uses the construct named in the lesson directly rather than reusing a generic placeholder.

Trace the example from its inputs through Custom exceptions and identify the behavior that would change if that construct were removed or replaced. Pay attention to the language-specific rules shown by the syntax, because neighboring lessons intentionally exercise different mechanisms.

Topic-specific example

elixir-0049-d711202950.exs
elixir Try It Live 
values = [50, 51, 52]
IO.inspect(Enum.sum(values)) # Custom exceptions
Edge case / engineering note

For Custom exceptions, test one realistic boundary: empty data, invalid input, unavailable resources, lifetime/cleanup, type constraints, or concurrency timing where applicable. A successful happy path is not enough to prove the construct is used correctly.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

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