[Gretl-devel] coupla things

Two new things in CVS that I think should be uncontroversial, but please let me know if any breakage results: * Up till now it has been impossible to give a scalar parameter to a user-defined function a default value of NA. This is partly because NA was used as the internal representation for "no value set". However, it seemed to me that in some cases it may be useful to set a default of NA for a trailing parameter, meaning that if the user omits a value for that parameter, it should then be ignored (not used) within the function. This is now possible, but note, only for parameters of type "scalar", not "bool" or "int". * Evaluation of boolean "&&" and "||": up till now we have evaluated both sides of these booleans before creating the result. But evaluation of the right-hand branch is redundant if (a) the operator is && and the left is FALSE, or (b) the operator is || and the left is TRUE. Now we skip evaluation on the right when it's redundant. Besides being more efficient this fixes a problem with NAs. Let the scalars x = 2, y = NA. Before the change if x > 1 || y > 10 would produce an error, since "y > 10" can't be evaluated. Now it works OK. Allin