
The macro tt(TYPEOUT) requires one parameter list. The text of the list is
sent to the standard error stream, followed by a newline. This feature can be
handy to show, e.g., messages such as version numbers in macro package files. 

Example: The following macro includes a file and writes to the screen that
this file is currently processed.

verb(
DEFINEMACRO(includefile)(1)(\ 
    TYPEOUT(About to process document: ARG1)\ 
    INCLUDEFILE(ARG1)))

