SD - The Open Source Multivalue String Database
Format: ASSIGNED(varname)
Returns 1 if variable varname is assigned a value, 0 if unassigned.
SDBasic variables are initially unassigned, except those in common blocks.
Unassigned variables will cause a runtime error.
SD Basic Functions - ARG()
OpenQM 2.6.6 documentation for this command is available here. The OpenQM documentation may provide additional context for this command. However, some features in SD have been modified so the OpenQM information may not be 100% applicable to SD.