Abbreviated notation for bases and elements

 

It is often useful to be able to use abbreviations for collections to be used in constructing other collections. In particular, we may like to use a base name that we supply as an argument to some of the commands listed at the beginning of the section in different ways. To do this we introduce a particular notation, which applies to the bases named in the definition part of the ADJUST: , TESTGRID: , BASE: , XBASE: , XGRID: , and LOOK:  (with argument b ) commands. (For the ADJUST:  command, see also §9.1.2.)

For these commands, a base D can appear as D, <D>, or , with the following interpretation.

D:

This is the simplest usage, and means the base D, is added as itself.

<D>:

This means that the base D is replaced by its constituent bases and elements, in alphabetical order. The notation applies only to a single base, so the notation is not allowed. As an example, if where are elements and are bases, then

:

This means that the base D is replaced by its constituent elements in alphabetical order. Any bases contained in D are likewise replaced by their consituents and so forth, recursively, until only a collection of elements is left. The notation applies only to a single base, so the notation is not allowed. As an example, suppose that where are elements and are bases, where contains the elements and contains the element . Then

For the remaining commands listed at the beginning of this section, that is the XDATA: , XELEMENT: , SHOW: , COHERENCE: , SUMMARY: , EXPORT: , and CENTRE: , commands, and the remaining usages for the LOOK:  command, any use of abbreviation notation is ignored. Each of these commands requires eventually a simple list of elements, so any base names given in their definition parts are simply replaced by their constituent parts, recursively replacing all constituent bases as appropriate.