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Array fold pattern

Learn Array fold pattern in Q# with a construct-specific explanation, a unique example, a practical boundary, and a mastery check.

12 min read • Advanced

Array fold pattern is an atomic Q# topic inside Data & Libraries. The example below uses the actual construct named by the lesson rather than a generic placeholder.

Focus on what Array fold pattern changes: the input, binding, control path, object state, collection, runtime effect, or language contract. Then alter one value and verify that the behavior changes for a reason specific to this feature.

Topic-specific example

qsharp-07-05-array-fold-pattern.qs
qsharp Try It Live 
function Sum(xs : Int[]) : Int { return Fold((s,x) -> s + x, 0, xs); }
Edge case / engineering note

Check the input collection shape, whether the operation mutates or returns a new value, and what happens for an empty collection.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

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