TESTCOND()      Test a condition or expression for validity
     Usage         Testcond(<cond>,<type>)
     Param         <cond>              condition to test
                   <type>              type of test to do

                   L - LOGICAL EXPRESSION    i.e.  DOGS=CATS
                   C - CHARACTER EXPRESSION  i.e.  lname+ltrim(fname)

     Example       if testcond("DOGS=CATS=MONKEYS","L")
                   if testcond("lastname=firstname'","C")

     Purpose       Allows testing of a condition to see if its a valid
                   condition without crashing the system. Used in clab()
                   to ensure .lbl selected matches current DBF, and also
                   in CB.PRG to ensure selected index matched current
                   DBF. An advanced version of QUERY() allows ad hoc
                   editing of the query condition and uses TESTCOND()
                   to test the condition's validity. (future release)

                   THIS WILL NOT WORK IF THE MODIFIED ERRORSYS SUPPLIED
                   IS NOT LINKED IN

                   i.e. TLINK prog,errorsys.obj,,,clipper extend super

     Assumes       THAT MODIFIED ERRORSYS.OBJ HAS BEEN LINKED IN
                            (see errorsys.prg)