command lineprocessing
When FunnelWeb reads in a command line (from the console or a script file),
it processes it in the following sequence:
- The command line is checked for non-printable characters. If there
are any, they are flagged with a severe error.
- All dollar string substitution variables in the command line are
replaced by their corresponding string.
The command line is processed from left to right. Substitutions are
performed non recursively.
- At this point, if the line is empty, or consists entirely of
blanks, it is ignored and the interpreter moves to the next line.
- A severe error is generated if the line at this stage begins with
a blank.
- If the first character of the line is !, the line is a
comment line and is ignored.
- The run of non-blanks commencing at the start of the line is
compared case-insensitively to each of the legal command verbs. If the
command is illegal, a severe error is generated, otherwise the command
is processed.