====== Reader's Clinic=====

^Published By^Date^Version^Knowledge Level^Keywords^
|Sprezzatura Ltd|01 JUL 1991|2.03+|EXPERT|RLIST, @USERNAME, VERBS, V39, @SENTENCE|

Michael Tucker of Nationwide Formal Wear called recently with an interesting
query. One of his users wanted to embed the current user name/account
name/other variable into the RLIST heading. This turned out to have two
possible solutions.

==== Break-On Solution ====

Create a symbolic in the dict of VOC called UNAME and make the formula @ANS
= @USERNAME. Ensure that the length is explicitly set to 0. Then in the list
statement include a construct similar to the following

<code>
:LIST USERS UNAME BREAK-ON UNAME "'B'" CO.NAME HEADING "'B'"
</code>

This will include the symbolic in the heading but not in the list statement.
This solution has two problems - a separate symbolic dictionary item must be
created for each value to be inserted, and it also slows down reporting.

==== V39 Solution ====

Subscribers to Volume 1 will remember that the ability to embed ?Prompts?
within any TCL statement still exists in AREV. This is handled by the V39
processor. This routine may be intercepted and put to more flexible use. To
try this method first back up your system!

<code>
COPY VERBS $V39 TO:$V39_RTI 
</code>

then create a subroutine as follows

<code>
       subroutine V39(FLAG)
          swap "?%U%?" with @USERNAME in @SENTENCE
          swap "?%A%?" with @ACCOUNT in @SENTENCE
          call V39_RTI(FLAG)
       return
</code>

compile it and COPY BP $V39 to(VERBS (N. The user then can then be
instructed to

<code>
:LIST USERS CO.NAME HEADING "?%U%?"
</code>

replacing the ?%U%? with any other variable you wish to intercept in V39.
NB to ensure that V39 is called, the RLIST sentence MUST contain ?. However
the replacement V39 can swap strings other than those ? delimited if
required. Note also that if the ?%U%? construct is used outside of the
HEADING statement the system will expect it to be in quotes - thus the above
code would need to be modified in account of this.

A powerful extension of this technique may be used when the user wishes to
list against a table where codes are stored referring to another table. The
user might not remember the codes (especially in the case of organisations,
contacts etc) but could remember the name. In this case the replacement V39
could scan for a special keyword (?%ORG%? or such like) and call a collector
window to assist the user in finding the required codes and then return
these codes into @SENTENCE. Thus the user is given the freedom to create
flexible RLIST enquiries which incorporate sophisticated lookup logic.


(Volume 3, Issue 3, Page 15)