This Technical Report provides a DSSSL library that can specify styles for the documents described by SGML (Standard Generalized Markup Language, ISO 8879) or XML (Extensible Markup Language, W3C REC-xml-980210). The library makes it feasible to describe DSSSL specification for those documents, without any particular knowledge of DSSSL or particular composition rules. The library deals with some complex compositions described by a number of complicated DSSSL specification statements. They are typically required in fixed-pitch document styles. Some of them can be applied to proportional pitch styles and fixed/proportional mixtures as well. More sophisticated compositions will be dealt with in a future Technical Report to be submitted.