Iterator operator: automatic temporary variables _index and _count changed with '__' and '_#' respectively. Note that, sinc '#' is not an identifier allowed char, '_#' requires himBHsnotation: -cover

operator-filter.go

@@ -43,8 +43,8 @@ func evalFilter(ctx kern.ExprContext, opTerm *term) (v any, err error) {
 	values := kern.NewListA()
 	for item, err = it.Next(); err == nil; item, err = it.Next() {
 		ctx.SetVar("_", item)
-		ctx.SetVar("_index", it.Index())
-		ctx.SetVar("_count", it.Count())
+		ctx.SetVar("__", it.Index())
+		ctx.SetVar("_#", it.Count())
 		if rightValue, err = opTerm.children[1].Compute(ctx); err == nil {
 			if success, valid := kern.ToBool(rightValue); valid {
 				if success {
@@ -54,8 +54,8 @@ func evalFilter(ctx kern.ExprContext, opTerm *term) (v any, err error) {
 				err = fmt.Errorf("filter expression must return a boolean or a castable to boolean, got %v [%T]", rightValue, rightValue)
 			}
 		}
-		ctx.DeleteVar("_count")
-		ctx.DeleteVar("_index")
+		ctx.DeleteVar("_#")
+		ctx.DeleteVar("__")
 		ctx.DeleteVar("_")
 		if err != nil {
 			break