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F# / Functions

Tail recursion

Learn Tail recursion in F# through a focused explanation, a dedicated topic-specific example, an engineering boundary, and a mastery check.

10 min read • Beginner

Tail recursion is a focused F# lesson inside Functions. The example uses the construct named in the lesson directly rather than reusing a generic placeholder.

Trace the example from its inputs through Tail recursion 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

fsharp-0018-450ce49621.fsx
fsharp Try It Live 
let values19 = [19; 20; 21]
printfn "%d" (List.sum values19) // Tail recursion
Edge case / engineering note

For Tail recursion, 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

Tail recursion Mastery Check →
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