Function ExplainPropertyListNested

src/backend/commands/explain.c:5437–5477

* Explain a property that takes the form of a list of unlabeled items within * another list. "data" is a list of C strings. */

 * another list.  "data" is a list of C strings.
 */
void
ExplainPropertyListNested(const char *qlabel, List *data, ExplainState *es)
{
	ListCell   *lc;
	bool		first = true;

	switch (es->format)
	{
		case EXPLAIN_FORMAT_TEXT:
		case EXPLAIN_FORMAT_XML:
			ExplainPropertyList(qlabel, data, es);
			return;

		case EXPLAIN_FORMAT_JSON:
			ExplainJSONLineEnding(es);
			appendStringInfoSpaces(es->str, es->indent * 2);
			appendStringInfoChar(es->str, '[');
			foreach(lc, data)
			{
				if (!first)
					appendStringInfoString(es->str, ", ");
				escape_json(es->str, (const char *) lfirst(lc));
				first = false;
			}
			appendStringInfoChar(es->str, ']');
			break;

		case EXPLAIN_FORMAT_YAML:
			ExplainYAMLLineStarting(es);
			appendStringInfoString(es->str, "- [");
			foreach(lc, data)
			{
				if (!first)
					appendStringInfoString(es->str, ", ");
				escape_yaml(es->str, (const char *) lfirst(lc));
				first = false;
			}
			appendStringInfoChar(es->str, ']');
			break;
	}
}

/*
 * Explain a simple property.