This library appears to escape forward slashes, which is fine, but it does not unescape them when parsing. This causes an error where the library sees the backslash escape, but doesn't find a forward slash in its is_control_character() function. This appears to cause it to go into escape mode because of the backflash, but having not found a control character it then suffers from error when parsing a string. Adding the forward slash to the switch statement in is_control_character() fixes the issue.
This library appears to escape forward slashes, which is fine, but it does not unescape them when parsing. This causes an error where the library sees the backslash escape, but doesn't find a forward slash in its is_control_character() function. This appears to cause it to go into escape mode because of the backflash, but having not found a control character it then suffers from error when parsing a string. Adding the forward slash to the switch statement in is_control_character() fixes the issue.