Add LATERAL query support

postgres/lateral.go

@@ -2,9 +2,19 @@ package postgres
 
 import "github.com/go-jet/jet/v2/internal/jet"
 
-func LATERAL(selectStmt SelectStatement, alias string) SelectTable {
+func LATERAL(selectStmt SelectStatement) lateralImpl {
+	return lateralImpl{
+		selectStmt: selectStmt,
+	}
+}
+
+type lateralImpl struct {
+	selectStmt SelectStatement
+}
+
+func (l lateralImpl) AS(alias string) SelectTable {
 	subQuery := &selectTableImpl{
-		SelectTable: jet.NewLateral(selectStmt, alias),
+		SelectTable: jet.NewLateral(l.selectStmt, alias),
 	}
 
 	subQuery.readableTableInterfaceImpl.parent = subQuery

postgres/lateral_test.go

@@ -3,7 +3,12 @@ package postgres
 import "testing"
 
 func TestLATERAL(t *testing.T) {
-	assertSerialize(t, LATERAL(SELECT(Int(1)), "lat1"), `LATERAL (
+	assertSerialize(t,
+		LATERAL(
+			SELECT(Int(1)),
+		).AS("lat1"),
+
+		`LATERAL (
      SELECT $1
 ) AS lat1`)
 }