org.apache.tapestry5.func
Interface LazyFunction<T>

public interface LazyFunction<T>

A lazy function is used to populate a Flow incrementally. Lazy functions allow calculations to be deferred. They also support infinitely large Flows, where successive values are computed just as needed.

Since:

5.2.0

Method Summary

LazyContinuation<T>

next() Calculates the next value for the function.

Method Detail

next

LazyContinuation<T> next()

Calculates the next value for the function. The return value is tricky: it combines the next value in the Flow with a function to compute the value after that as a LazyContinuation. Alternately, a LazyFunction can return null to indicate that it has returned all the values it can.

Returns:

continuation containing next value and next function, or null when no more values can be produced