XML::Checker ERROR-100: undefined NOTATION [undef_notation] in ATTLIST
	Context: Element p, Attr notation
XML::Checker ERROR-151: only one ID allowed per ELEMENT first=[req_id]
	Context: Element q, Attr second_id
XML::Checker ERROR-123: invalid default ID [1bad_default_id], must be #REQUIRED or #IMPLIED
	Context: Element bad_id, Attr bad_default_id
XML::Checker ERROR-120: invalid default IDREF [1bad_default_idref]
	Context: Element bad_id, Attr bad_default_idref
XML::Checker ERROR-121: invalid default [1bad_default_idrefs] in IDREFS [1bad_default_idrefs default_id]
	Context: Element bad_id, Attr bad_default_idrefs
XML::Checker ERROR-120: invalid default ENTITY [1bad_default_ent]
	Context: Element bad_ent, Attr bad_default_ent
XML::Checker ERROR-121: invalid default [1bad_default_idref] in ENTITIES [1bad_default_idref default_entity]
	Context: Element bad_ent, Attr bad_default_ents
XML::Checker ERROR-159: unspecified value for #REQUIRED attribute [second_id]
	Context: Element q, Attr second_id
XML::Checker ERROR-150: bad #FIXED attribute value [bad fixed value], it should be [fixed value]
	Context: Element p, Attr fixed
XML::Checker ERROR-160: invalid Enumeration value [bad enum]
	Context: Element p, Attr enum
XML::Checker ERROR-157: unexpected Element [unexpected]
	Context: ChildElementIndex 0
XML::Checker ERROR-157: unexpected Element [undefined]
	Context: ChildElementIndex 1
XML::Checker ERROR-101: undefined ELEMENT [undefined]
XML::Checker ERROR-159: unspecified value for #REQUIRED attribute [second_id]
	Context: Element q, Attr second_id
XML::Checker ERROR-130: invalid NMTOKEN [1bad nmtoken]
	Context: Element n, Attr nmtoken
XML::Checker ERROR-103: undefined attribute [bad_idref]
	Context: Element bad_id
XML::Checker ERROR-132: invalid IDREF [1bad_default_idref]
	Context: Element bad_id, Attr bad_default_idref
XML::Checker ERROR-132: invalid IDREF [1bad_default_idrefs]
	Context: Element bad_id, Attr bad_default_idrefs
XML::Checker ERROR-131: invalid ID [1bad_default_id]
	Context: Element bad_id, Attr bad_default_id
XML::Checker ERROR-132: invalid IDREF [1bad_default_idref]
	Context: Element bad_id, Attr bad_default_idref
XML::Checker ERROR-132: invalid IDREF [1bad_default_idrefs]
	Context: Element bad_id, Attr bad_default_idrefs
XML::Checker ERROR-131: invalid ID [1bad_default_id]
	Context: Element bad_id, Attr bad_default_id
XML::Checker ERROR-111: ID [1bad_default_id] already defined
	Context: Element bad_id, Attr bad_default_id
XML::Checker ERROR-133: invalid ENTITY name [1bad_default_ent]
	Context: Element bad_ent, Attr bad_default_ent
XML::Checker ERROR-102: undefined unparsed ENTITY [1bad_default_ent]
	Context: Element bad_ent, Attr bad_default_ent
XML::Checker ERROR-133: invalid ENTITY name [1bad_default_idref]
	Context: Element bad_ent, Attr bad_default_ents
XML::Checker ERROR-102: undefined unparsed ENTITY [1bad_default_idref]
	Context: Element bad_ent, Attr bad_default_ents
XML::Checker ERROR-103: undefined attribute [bad_ent]
	Context: Element bad_ent
XML::Checker ERROR-133: invalid ENTITY name [1bad_default_ent]
	Context: Element bad_ent, Attr bad_default_ent
XML::Checker ERROR-102: undefined unparsed ENTITY [1bad_default_ent]
	Context: Element bad_ent, Attr bad_default_ent
XML::Checker ERROR-133: invalid ENTITY name [1bad_default_idref]
	Context: Element bad_ent, Attr bad_default_ents
XML::Checker ERROR-102: undefined unparsed ENTITY [1bad_default_idref]
	Context: Element bad_ent, Attr bad_default_ents
XML::Checker WARNING-200: undefined ID [1bad_default_idrefs] was referenced [2] times
XML::Checker WARNING-200: undefined ID [1bad_default_idref] was referenced [2] times
XML::Checker INFO-300: [0] references to ID [1bad_default_id]
XML::Checker INFO-300: [4] references to ID [default_id]
XML::Checker INFO-300: [0] references to ID [unreferenced_id]