Due to the implementation of macros, there are new character sequences which are interpreted by HelpSetMaker itself. They are:
"((" and "))" in macro calls.
"{{" and "}}" for referencing a macro parameter inside the macro's body.
"|" as a seperator of macro parameters in the definition and in the call.
Note that the "|"-bar prints itself if it is used outside a macro call or the macro parameter list.
Furthermore, arrows are also built from character sequences which have been uninterpreted by HelpSetMaker before. For left ("<-") and right ("->") arrows, the chosen description as "<-" and "->" is more or less the natural way of representing an arrow with the default set of characters. Up- ("^") and downward ("v") arrows use "$^" and "$v", which should also be used only with very low density in normal texts...
To prevent HelpSetMaker from evaluating these character sequences and transform them into arrows, just prepend them with a backslash "\".