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Errors and I/O
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D / Errors and I/O

unit tests

Learn unit tests in D with a construct-specific explanation, unique example, engineering boundary, and mastery check.

10 min read • Advanced

unit tests 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 unit tests, then change one input and predict the result before running it.

Topic-specific example

d-08-09-unit-tests.d
d Try It Live 
unittest { assert(2+2==4); }
Edge case / engineering note

unit tests 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

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