TeX provides groups as a means to restrict the visibility of registers. This construction is well known in the TeX world but does not coincide with the groups as known from other pro­gram­ming languages. If we refrain from storing the re­gis­ter value in a global array we can come to the alternate solution of storing it in the control sequence used to access it. With this variant we can provide a means to define an arbitrary number of registers which follow the same scoping rules ike the variables in Pas­cal-like languages.

εχTeX is a re­im­ple­men­ta­ti­on of TeX in Java. It is developed with the extensibility and configurability in mind. The idea of an al­ter­na­ti­ve storage for registers can be implemented in εχTeX as an extension. It is shown which steps are required for such an im­ple­men­ta­tion. In this course the extensibility of εχTeX is demonstrated.