Function FuncNameAsType

src/backend/parser/parse_func.c:1935–1958

* FuncNameAsType - * convenience routine to see if a function name matches a type name * * Returns the OID of the matching type, or InvalidOid if none. We ignore * shell types and complex types. */

 * shell types and complex types.
 */
static Oid
FuncNameAsType(List *funcname)
{
	Oid			result;
	Type		typtup;

	/*
	 * temp_ok=false protects the <refsect1 id="sql-createfunction-security">
	 * contract for writing SECURITY DEFINER functions safely.
	 */
	typtup = LookupTypeNameExtended(NULL, makeTypeNameFromNameList(funcname),
									NULL, false, false);
	if (typtup == NULL)
		return InvalidOid;

	if (((Form_pg_type) GETSTRUCT(typtup))->typisdefined &&
		!OidIsValid(typeTypeRelid(typtup)))
		result = typeTypeId(typtup);
	else
		result = InvalidOid;

	ReleaseSysCache(typtup);
	return result;
}

/*
 * ParseComplexProjection -