Thank you for the clear explanation. > On Oct 24, 2021, at 1:05 AM, Michael Van Canneyt via fpc-pascal > <fpc-pascal@lists.freepascal.org> wrote: > > > > On Sat, 23 Oct 2021, P Padilcdx via fpc-pascal wrote: > >> Hello, >> >> Was trying to declare a procedure with an array argument, e.g. procedure >> p(a: array[1..9] of int64), and the compiler complained as it seems only >> accepts open arrays. If I set a type alias for the array, e.g. type t = >> array[1..9] of int64, then I can declare the procedure p(a: t). This >> behavior seems odd, why couldn’t I declare the procedure with a bounded >> array without having to declare a type alias first? > > You can never declare a new type in a procedure header. > For example you also cannot do > > procedure (a ; record x,y : integer; end); > or > procedure (a : (one,two,three)); > > The reason is type compatibility: the argument type is unknown outside the > procedure > and therefor the compiler will never allow you to assign something to it, > since there is no way to check if it is a compatible type, and you will not > be able to do a typecast as there is no type name to typecast with. > > An open array is simply an exception for this rule, allowing you to skip the > boundaries of the array. > > Michael._______________________________________________ > fpc-pascal maillist - fpc-pascal@lists.freepascal.org > https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
_______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
