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D / Errors and I/O

contracts in out do

Learn contracts in out do in D with a construct-specific explanation, unique example, engineering boundary, and mastery check.

10 min read • Advanced

contracts in out do is a focused D topic inside Errors and I/O. This lesson explains the construct itself, the state or value it operates on, and the observable result it produces.

Read the example as a small executable experiment. Identify the exact syntax that belongs to contracts in out do, then change one input and predict the result before running it.

Topic-specific example

d-08-10-contracts-in-out-do.d
d Try It Live 
int sqrtish(int x) in(x>=0) out(result; result>=0) do { return x; }
Edge case / engineering note

contracts in out do has rules that are easy to miss when the example is copied mechanically. Check the feature-specific boundary shown by this construct: scope, mutability, evaluation order, type constraints, lifetime, error behavior, compile-time restrictions, or resource cleanup where applicable.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

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