Module com.darkcollective.relix.ast

Package com.darkcollective.relix.ast

Interface WindowFunction

All Known Implementing Classes:

WindowFunction.AggregateWindow, WindowFunction.OffsetWindow, WindowFunction.RankingWindow

public sealed interface WindowFunction
permits WindowFunction.AggregateWindow, WindowFunction.RankingWindow, WindowFunction.OffsetWindow

The computation a WindowNode performs per row. A single sealed hierarchy covers all three window families; the permit encodes what differs while WindowNode holds what they share (partition keys, sort specs, frame, output column).

• WindowFunction.AggregateWindow — sliding / cumulative aggregates (SUM, AVG, COUNT, MIN, MAX); introduced by the ROLLING keyword (slice 2).
• WindowFunction.RankingWindow — ranking functions (ROW_NUMBER, RANK, …); WINDOW keyword (slice 3).
• WindowFunction.OffsetWindow — offset functions (LAG, LEAD, FIRST_VALUE, LAST_VALUE); WINDOW keyword (slice 4).

All three forms are permitted by the one sealed interface, so every switch over a window function is exhaustive and a consumer cannot silently ignore a form it does not handle.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static final record	WindowFunction.AggregateWindow	A sliding / cumulative aggregate over an Operand argument — the same AggregateOperator + Operand pair used by γ.
static final record	WindowFunction.OffsetWindow	An offset function (slice 4).
static final record	WindowFunction.RankingWindow	A ranking function (slice 3).