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D / Templates

template constraints

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

10 min read • Intermediate

template constraints is a focused D topic inside Templates. 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 template constraints, then change one input and predict the result before running it.

Topic-specific example

d-04-03-template-constraints.d
d Try It Live 
T clampZero(T)(T x) if (is(T : long)) { return x < 0 ? 0 : x; }
Edge case / engineering note

template constraints 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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