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Q# Complete Course / Classical Control

while loop

Learn while loop in Q# with a construct-specific explanation, a unique example, a practical boundary, and a mastery check.

10 min read • Beginner

while loop is an atomic Q# topic inside Classical Control. The example below uses the actual construct named by the lesson rather than a generic placeholder.

Focus on what while loop 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-02-03-while-loop.qs
qsharp Try It Live
operation Demo() : Int { mutable n = 3; while n > 0 { set n -= 1; } return n; }
Edge case / engineering note

Change the key input in this Q# example and predict the result first; the named construct should be the reason the behavior changes.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content