Serialization is intended primarily as a component of a host language. [Definition: A host language is another specification that includes, by reference, this specification and all of its requirements. A host language might be a programming language such as [XSL Transformations (XSLT) Version 3.0] or [XQuery 3.1: An XML Query Language], or it might be an application programming interface (API) intended to be used by programs written in some other high-level programming language. The use of the term language is not intended to preclude the possibility that this specification might be referenced outside the context of a programming language specification.] This document relies on specifications that use it to specify conformance criteria for Serialization in their respective environments. Specifications that set conformance criteria for their use of Serialization MUST NOT change the semantic definitions of Serialization as given in this specification, except by subsetting and/or compatible extensions. It is the responsibility of the host language to specify how serialization errors are to be handled.
Certain facilities in this specification are described as producing implementation-defined results. A claim that asserts conformance with this specification MUST be accompanied by documentation stating the effect of each implementation-defined feature. For convenience, a non-normative checklist of implementation-defined features is provided at E.1 Checklist of Implementation-Defined Features.