/** @file mf_existfeature.sas @brief Checks whether a feature exists @details Check to see if a feature is supported in your environment. Run without arguments to see a list of detectable features. Note - this list is based on known versions of SAS rather than actual feature detection, as that is tricky / impossible to do without generating errors in most cases. %put %mf_existfeature(PROCLUA); @param feature the feature to detect. Leave blank to list all in log. @return output returns 1 or 0 (or -1 if not found)