6.36. restrict Macro
The general syntax is:
The arguments are:
See Understanding Macro Interfaces, if necessary.
The restrict macro declares a restricted family of variables. If a variable begins with a restricted prefix, then it must be declared via the define filter.
This feature aims to catch errors caused by authors using a bad variable name. For example, if an author types
!define DOC_NAMe "My Document"
but meant to type
!define DOC_NAME "My Document"
then an error will be raised as DOC_NAMe is an unknown variable within the DOC family.