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Contract Programming

Contracts enable specifying conditions that must hold true when the flow of runtime execution reaches the contract. If a contract is not true, then the program is assumed to have entered an undefined state.


Building contract support into the language provides:

  1. a consistent look and feel for the contracts
  2. tool support
  3. the implementation can generate better code using information gathered from the contracts
  4. easier management and enforcement of contracts
  5. handling of contract inheritance
Contracts make D bug resistant

Assert Contract

See AssertExpression.

Pre and Post Contracts



See Struct Invariants and Class Invariants.


Template Mixins
Conditional Compilation