Custom aggregate functions.

context.go

@@ -14,6 +14,7 @@ import (
 type Context struct {
 	*module
 	handle uint32
+	final  bool
 }
 
 // ResultBool sets the result of the function to a bool.
@@ -154,4 +155,27 @@ func (c *Context) ResultError(err error) {
 		c.call(c.api.resultErrorCode,
 			uint64(c.handle), uint64(xcode))
 	}
+
+}
+
+func AggregateContext[T any](ctx Context) *T {
+	var size uint64
+	if !ctx.final {
+		size = ptrlen
+	}
+	pAgg := uint32(ctx.call(ctx.api.aggregateData, uint64(ctx.handle), size))
+	if pAgg == 0 {
+		return nil
+	}
+	pData := util.ReadUint32(ctx.mod, pAgg)
+	if data := util.GetHandle(ctx.ctx, pData); data != nil {
+		return data.(*T)
+	}
+	if ctx.final {
+		return nil
+	}
+	data := new(T)
+	pData = util.AddHandle(ctx.ctx, data)
+	util.WriteUint32(ctx.mod, pAgg, pData)
+	return data
 }