Lorenzo,
There was a breakdown in communications. Were you informed of my objections to LAYER_NUM? Dick On 04/08/2013 01:17 PM, Lorenzo Marcantonio wrote: > On Mon, Apr 08, 2013 at 12:22:03PM -0500, Dick Hollenbeck wrote: >> We don't need a special type for each usageof an integer. > It's here exactly for type safety. Even pointer are integers, in fact > BCPL (the progenitor of C) used ints as pointer. Still some toolkit > force you to fit pointer into ints (which isn't even legal in C!) > But a layer id is *only* a layer id, you can't do math with it and so > on. In fact in my private branch LAYER_NUM is an enum just like > LAYER_MSK. In the past I fixed bugs (and comments, and variable names) > where reading from the code a mask would be passed when in fact it was > a layer id. C++11 has added features to inhibit the enum to integer > default promotion, just to say how much the technique is useful... would > you use only void* for pointers? > > Read here: > http://www.cprogramming.com/c++11/c++11-nullptr-strongly-typed-enum-class.html > > enums also can't take "invalid" values unless casted; that avoid checks > everywhere for their correctness. I have a LayerToInt for the (rare) > cases where such cast is needed (actually only in I/O and for user > interface indexed). Oh and, by the way, that made me found the evil > encoding of a layer pair for vias... I still have to fix it, I need to > study the code better for that. That's one of the reason for not > committing the whole LAYER_NUM modification (the other one is that I'm > still not happy with the enum representation). > > In some project they go to the extreme to typedef even different > coordinates system, i.e. logical coords are a type and physical coords > are another; in that way you *can't* use the wrong reference system. In > ADA even if you typedef to an int you get a whole different type > *incompatible* to an int (that's a really static type system...) > > It's more useful anyway than encapsulating a variable with public getter > and setter that don't do nothing special. > _______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
