Function raw_expression_tree_walker

src/backend/nodes/nodeFuncs.c:3825–4300

* raw_expression_tree_walker --- walk raw parse trees * * This has exactly the same API as expression_tree_walker, but instead of * walking post-analysis parse trees, it knows how to walk the node types * found in raw grammar output. (There is not currently any need for a * combined walker, so we keep them separate in the name of efficiency.) * Unlike expression_tree_walker, there is no spe

 * appear in CTEs.
 */
bool
raw_expression_tree_walker(Node *node,
						   bool (*walker) (),
						   void *context)
{
	ListCell   *temp;

	/*
	 * The walker has already visited the current node, and so we need only
	 * recurse into any sub-nodes it has.
	 */
	if (node == NULL)
		return false;

	/* Guard against stack overflow due to overly complex expressions */
	check_stack_depth();

	switch (nodeTag(node))
	{
		case T_SetToDefault:
		case T_CurrentOfExpr:
		case T_SQLValueFunction:
		case T_Integer:
		case T_Float:
		case T_String:
		case T_BitString:
		case T_Null:
		case T_ParamRef:
		case T_A_Const:
		case T_A_Star:
			/* primitive node types with no subnodes */
			break;
		case T_Alias:
			/* we assume the colnames list isn't interesting */
			break;
		case T_RangeVar:
			return walker(((RangeVar *) node)->alias, context);
		case T_GroupingFunc:
			return walker(((GroupingFunc *) node)->args, context);
		case T_GroupId:
		case T_GroupingSetId:
			break;
		case T_SubLink:
			{
				SubLink    *sublink = (SubLink *) node;

				if (walker(sublink->testexpr, context))
					return true;
				/* we assume the operName is not interesting */
				if (walker(sublink->subselect, context))
					return true;
			}
			break;
		case T_CaseExpr:
			{
				CaseExpr   *caseexpr = (CaseExpr *) node;

				if (walker(caseexpr->arg, context))