Hello, I found out that if you use the constructor function::function(unsigned ser, const exprseq & es) to construct a function, this function does not get evaluated if the exprseq was already evaluated. The reason is that the expression sequence is copied with the exprseq::copy function and that this takes over the status flags of the already-evaluated exprseq. Therefore I think that the function function::function(unsigned ser, const exprseq & es) : exprseq(es), serial(ser) { tinfo_key = TINFO_function; } that occurs in the script function.pl should be changed into function::function(unsigned ser, const exprseq & es) : exprseq(es), serial(ser) { tinfo_key = TINFO_function; flags = flags & ~status_flags::evaluated; } All the best, Chris Dams