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0 pointsPxtl11y ago0 comments

They're doing dictionaries in CS6.

0 comments

That's sad. They should do tuples and top-level functions and solve it naturally.

PxtlOP11y ago

They are doing a hack for top-level functions - they're adding "using" for static classes so you can pull all the static methods of a class into the local namespace. Don't see how that would help for dictionaries, though.

The ugly part of the dictionary is the type parameters, but I can't see a workaround for that without some really hard type-inferencing for all generics. I mean, you'd have to infer the type-parameters of a generic class based on the type-parameter of the IEnumerable passed into its constructor (dictionary takes an IEnumerable of KeyValuePairs of TKey, TValue). That's a little messy.

MichaelGG11y ago

I was alluding to F#'s handling:

  > let myd = dict [ "a", 1; "the", 2; "train", 3 ];;
  val myd : System.Collections.Generic.IDictionary<string,int>

  > let myd = dict [ "a", System.String.IsNullOrEmpty ];;
  val myd : System.Collections.Generic.IDictionary<string,(string -> bool)>

If C# had tuples, then you might be able to do something like:

  var myd = createdict(new[] { {"a", 1} , { "the", 2} ...})

The tuples should get a type inferred, then the array, then that can pass the type to createdict and all good. And the array could be removed if there was some other sort of list-like literal. This might be really difficult to implement in the C# compiler, for all I know.

More likely, they'll graft in yet another special rule in the compiler (not accessible to user code!), just as they did with other collections, foreach, async, etc. I find it ugly that the compiler is happy to use static duck typing when convenient, but such a feature isn't exposed in the language.

j / k navigate · click thread line to collapse

0 comments

MichaelGG11y ago

That's sad. They should do tuples and top-level functions and solve it naturally.

PxtlOP11y ago

MichaelGG11y ago

I was alluding to F#'s handling:

  > let myd = dict [ "a", 1; "the", 2; "train", 3 ];;
  val myd : System.Collections.Generic.IDictionary<string,int>

  > let myd = dict [ "a", System.String.IsNullOrEmpty ];;
  val myd : System.Collections.Generic.IDictionary<string,(string -> bool)>

If C# had tuples, then you might be able to do something like:

  var myd = createdict(new[] { {"a", 1} , { "the", 2} ...})

j / k navigate · click thread line to collapse