<- [[.:prplreference| PRPL reference]] <- [[.:prplreference#vars_and_functions|Vars and Functions]] ===== -?! (Ref Exists) ===== ^Arguments^Result^Notation^ | name | bool | [ string - bool ] | === Description === name : The string name of the heap variable to check. Takes a string from the stack and uses it as a variable name. Checks to see if the variable exists (has been assigned). If so, 1 is pushed to the stack else 0. === Examples === 42 ->somevar trace(-?!("somevar"))