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Anonymous functions Named functions Default arguments Multiple function clauses Private functions Pipe operator Capture operator Recursion Tail recursion Higher-order Enum functions
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Spawning processes Sending messages Receive blocks Process links Process monitors Task.async Task.await Agent state GenServer calls GenServer casts
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Supervisor child specs One-for-one strategy DynamicSupervisor Registry Application module Process naming Timeout handling Terminate callbacks ETS tables Persistent term
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Elixir / Functions and Pipelines

Capture operator

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

10 min read • Beginner

Capture operator is a focused Elixir lesson inside Functions and Pipelines. The example uses the construct named in the lesson directly rather than reusing a generic placeholder.

Trace the example from its inputs through Capture operator 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-0017-537ee2683a.exs
elixir Try It Live 
values = [18, 19, 20]
IO.inspect(Enum.sum(values)) # Capture operator
Edge case / engineering note

For Capture operator, 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

Capture operator Mastery Check →
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