Dear GiNaC developer, I'm using GiNaC version 1.6.2 with compiler gcc (Ubuntu/Linaro 4.5.2-8ubuntu4) 4.5.2 When working with the parser to read in user defined functions from strings I noticed 3 things: 1) parsing a user defined function (declared to have 1 argument) from a string does not throw an exception when the string contains this function with zero arguments. 2) parsing products of user defined non-commutative functions returns a commutative product 3) The parser accepts userdefined functions with zero arguments and parsing such a function does not throw when there is 1 argument. I have attached a small file "main.cpp" such that you can reproduce this behavior. I'm using these user defined functions with zero arguments but it looks to me like a hack and I would like to know if you are going to allow them ( e.g. with macro definition) or if you completely suppress them in future releases of GiNaC. Thank you very much! Cedric Studerus