On 22 Oct 2010, at 21:35, Hans-Peter Diettrich wrote: > Jonas Maebe schrieb: > >>> What's the guarantee, that (in detail external) subroutines will honor the >>> "const" attribute? >> None. "const" (and constref) is a hint from the programmer that the argument >> can be considered by the compiler as "constant" inside the called routine. > > What about reference counting or similar stuff, that differs for const and > other arguments?
It's the same for const and constref. >>> In how far does "constref" affect the *caller*, in contrast to e.g. "var"? >>> Can constref pass properties, which are not allowed as var parameters? >> Right now it's allowed (if the property uses a getter, the getter is called >> and its result is put into a temp location whose address is passed), but I >> think that's a bug in the implementation. > > When this feature is removed, does there remain any difference between var > and constref, at the calling side? At least you cannot pass a const parameter to a var parameter, while you can pass a const parameter to a constref parameter. Since it's always possible to take the address of a const parameter (unlike of a property), this is semantically consistent. Jonas_______________________________________________ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
