2.2.4 [W3C-XSS] Section 4.1, Layer 1: Summary of the Schema-validity Assessment Core
Processors have the option to assemble (and perhaps to optimize or pre-compile) the entire schema prior to the start of an ·assessment· episode, or to gather the schema lazily as individual components are required. In all cases it is required that: - The processor succeed in locating the ·schema components· transitively required to complete an ·assessment· (note that components derived from ·schema documents· can be integrated with components obtained through other means);
§ no definition or declaration changes once it has been established; § if the processor chooses to acquire declarations and definitions dynamically, that there be no side effects of such dynamic acquisition that would cause the results of ·assessment· to differ from that which would have been obtained from the same schema components acquired in bulk.
The SchemaCache object does not acquire declarations and definitions dynamically.
Note: the ·assessment· core is defined in terms of schema components at the abstract level, and no mention is made of the schema definition syntax (i.e. <schema>). Although many processors will acquire schemas in this format, others may operate on compiled representations, on a programmatic representation as exposed in some programming language, etc.
The SchemaCache object does not operate on compiled representations or on a programmatic representation. SchemaCache acquires schemas only in schema document format.