Pascakondisi

Pascakondisi is the Indonesian term for a postcondition in software engineering. It is a logical assertion that must hold after a procedure, function, or operation finishes, assuming its preconditions were met. Pascakondisi describes the expected outcome and the resulting state of the system.

Pascakondisi is typically contrasted with preconditions (syarat-prasyarat), which specify what must be true before execution. Together, preconditions and pascakondisi form part of the contract-based approach known as design by contract, where a function or method commits to certain guarantees if its inputs meet the stated prerequisites.

In practice, a pascakondisi may express constraints about a return value, state changes, or relationships between variables. For example, a function add(a, b) might have a postcondition that the result equals a plus b, and that the inputs remain unchanged if they are passed by value. In a banking operation, a withdraw(x) might have a precondition that x is positive and less than or equal to the available balance, and a postcondition stating that the new balance equals the old balance minus x and that the operation reports success.

Pascakondisi can be formalized using logical predicates or formal specification languages and is used in various programming environments that support design by contract, such as Eiffel, or through assertion mechanisms and specification languages like JML, Spec#, or ACSL. Limitations arise when preconditions are not met, which can render postconditions invalid or meaningless.