Control sequence definitions for Registers.
These are set up as a speciallized primitive with a getter and setter to access and store values in the Stomach. See LaTeXML::Package for the most convenient means to create them.
It extends LaTeXML::Core::Definition::Primitive.
Registers generally store some value in the current LaTeXML::Core::State, but are not required to. Like TeX’s registers, when they are digested, they expect an optional =, and then a value of the appropriate type. Register definitions support these additional methods:
Return the value associated with the register, by invoking it’s getter function. The additional args are used by some registers to index into a set, such as the index to count.
Assign a value to the register, by invoking it’s setter function.