Re: Named parameters in function call
On Wednesday, 9 September 2020 at 11:48:28 UTC, Paul Backus wrote:
On Tuesday, 8 September 2020 at 13:28:22 UTC, Cecil Ward wrote:
I wonder if there is any way in which we could combine this
with strong typing of some sort (how?) to detect errors such as
int xcoord;
int ycoord;
myfunc( x : ycoord, y : xcoord, color : blue )[3]
where the arguments are the wrong way around. Would have to
change the types of the xcoord and ycoord variables somehow,
something I have asked about earlier.
import std.typecons: Typedef;
alias XCoord = Typedef!(int, int.init, "XCoord");
alias YCoord = Typedef!(int, int.init, "YCoord");
auto myfunc(XCoord x, YCoord y) { ... }
Brilliant. Thank you Paul.
Re: Named parameters in function call
On Tuesday, 8 September 2020 at 13:28:22 UTC, Cecil Ward wrote:
I wonder if there is any way in which we could combine this
with strong typing of some sort (how?) to detect errors such as
int xcoord;
int ycoord;
myfunc( x : ycoord, y : xcoord, color : blue )[3]
where the arguments are the wrong way around. Would have to
change the types of the xcoord and ycoord variables somehow,
something I have asked about earlier.
import std.typecons: Typedef;
alias XCoord = Typedef!(int, int.init, "XCoord");
alias YCoord = Typedef!(int, int.init, "YCoord");
auto myfunc(XCoord x, YCoord y) { ... }
Re: Named parameters in function call
On Tuesday, 8 September 2020 at 13:28:22 UTC, Cecil Ward wrote:
int xcoord;
int ycoord;
You can define your own types, of course:
struct xcoord { int x; alias x this; }
struct ycoord { int y; alias y this; }
void myfunc(xcoord x; ycoord y, color c) {}
Re: Named parameters in function call
On Tuesday, 8 September 2020 at 09:40:11 UTC, Andre Pany wrote: On Tuesday, 8 September 2020 at 07:43:05 UTC, Cecil Ward wrote: I can’t remember, do Ada or Modula2 have something like myfunc( x => 100, y => 200, color => blue )[1] which has named parameters that can be passed in any order. [...] I hope we have it this year or next year, as we have this DIP https://www.github.com/dlang/DIPs/tree/master/DIPs%2FDIP1030.md Kind regards Andre I wonder if there is any way in which we could combine this with strong typing of some sort (how?) to detect errors such as int xcoord; int ycoord; myfunc( x : ycoord, y : xcoord, color : blue )[3] where the arguments are the wrong way around. Would have to change the types of the xcoord and ycoord variables somehow, something I have asked about earlier.
Re: Named parameters in function call
On Tuesday, 8 September 2020 at 07:43:05 UTC, Cecil Ward wrote: I can’t remember, do Ada or Modula2 have something like myfunc( x => 100, y => 200, color => blue )[1] which has named parameters that can be passed in any order. [...] I hope we have it this year or next year, as we have this DIP https://www.github.com/dlang/DIPs/tree/master/DIPs%2FDIP1030.md Kind regards Andre
