"NVAL" command allowes you to use named values. MapTool uses named values to store mapping information.

Full Syntax
<nval>name[<@>container]<endnval>
Short Syntax
%nval<name[<@>container]>
%nv<name[<@>container]>

Command can be used based on runtime support (GenProcessor). Default implementation of GenProcessor uses mapping information to return NVAL result.

Name formats used by default GenProcessor -