On Tuesday, 29 April 2014 at 08:21:04 UTC, John Colvin wrote:
On Monday, 28 April 2014 at 23:02:03 UTC, bearophile wrote:
I think it could be a good idea to add something intermediate
to D: optional strong typing for array indexing. I'd like to
write a DIP on this someday (note that this does not mean I am
suggesting D array indexes to optionally start from values
different from 0. I am referring just to types, and
enumerations are could be not supported).
Bye,
bearophile
Any reason why this needs language support? I haven't tried it,
but I can't see why it can't be trivially done in a library.
Pascal example:
type
colors = (red, blue, yellow);
var
pallete : array colors of integer;
begin
pallete[red] := 4;
end
You want a compiler error if the index is invalid and bounds
checking when iterating over the enumeration and using it as
indexes.
Probably possible with some heavy duty compile time
metaprogramming, not sure about the quality of possible error
messages and if it would cover all scenarios Pascal and Ada allow
for.
--
Paulo
