Is is possible to have mutually recursive functions that are also tail recursive? For example, attached is some code I wrote to flatten a list of lists using mutually recursive functions. I've tried this with large lists (5,000,000+) and have not encountered a stack overflow, but that does not necessarily mean that tail recursion is happening. Also, I know that there are ZAM opcodes that indicate a tail recursive function (TAILCALL, if I am not mistaken) and one or two of the undocumented compiler options will dump the opcodes. Could someone briefly explain what each of those options do so I wouldn't have to take up everybody's time asking if this is tail recursive? --Jonathan -- *=========================* |Jonathan Bryant | |Valdosta State University| |Information Technology | |System Operations | |-------------------------| |jtbryant@valdosta.edu | |x6358 | *=========================*