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> The TARGET tells the compiler to reserve storage, while the PARAMETER > tells it that it can assume that it will never change. Conceptually, > the two are orthogonal. The compiler can still perform constant > folding, it just has to keep one copy in memory. Normally, TARGET doesn't tell the compiler to reserve storage, since it is an attribute of a variable which has storage for it reserved anyway. It's main use is to let the compiler know what can in principle be aliased, so that one isn't left with the choice, as in C, to either not optimise or allow strange behaviour. Since PARAMETER doesn't imply storage, TARGET would have to tell the compiler to make it a "read-only variable", perhaps implementing it quite differently than would otherwise be the case. It could be done, of course, but would require a lot of implementations to change quite a bit with regard to PARAMETER, or else implement TARGET PARAMETERs as an additional case. These days, possible efficiency advantages of PARAMETER as opposed to variables are probably negligible. The main advantage is that the programmer cannot change their value by mistake. I agree that constants (the name PARAMETER is rather unfortunate) are conceptually quite different from variables, like the distinction, and want an error if I try to modify it, but in practice you could probably just have your tables be variables and make sure that you don't try to modify them in your code. This is similar to arrays of PARAMETERs in Fortran77. Since this feature didn't exist, one had to use variables, and just remember not to change them. -- Phillip Helbig Email .............. [log in to unmask] Kapteyn Instituut Email ................. [log in to unmask] Rijksuniversiteit Groningen Tel. ................... +31 50 363 6647 Postbus 800 Fax .................... +31 50 363 6100 NL-9700 AV Groningen Web ... http://www.astro.rug.nl/~helbig/ My opinions are not necessarily those of my employer. <A HREF=" http://gladia.astro.rug.nl:8000/helbig/hire/hire.html ">HIRE ME!</A> Reward: one month of salary (yours or mine---take your pick)! %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%