Consistency

[Xinok via Digitalmars-d]

On Sunday, 15 February 2015 at 17:18:08 UTC, Steve D wrote:
> Python (built-in)
>
> dict1 = {"a":1,"b":2}
> tup1  = (0,1,2,3)
> arr1  = [0,1,2,3]  # list type
> str1  = "abcd"
>
> print "b" in dict1    # True
> print 3 in tup1       # True
> print 3 in arr1       # True
> print "c" in str1     # True
>
> print tup1.index(2)   # 2
> print arr1.index(2)   # 2
> print str1.index("c") # 2
>
> There is some sort of consistency of use, though they are 
> different sequence/collection types.
>
> Now try the same in D
>
> auto dict1 = ["a":1,"b":2];
> auto tup1  = tuple(0,1,2,3);
> auto arr1  = [0,1,2,3];
> auto str1  = "abcd";
>
> Having some consistency involving 
> sequences/arrays/strings/collections etc, which are the 
> foundations of any language makes programming much easier, 
> intuitive and pleasant. It shouldn't be too difficult for a 
> super bare-metal language like D.
> I'm honestly not knocking D (I love it), just some thoughts 
> (maybe provoke some discussion?, for D3?)

Part of the issue is that "in" means to search by key, not by 
value. In that respect, it only makes sense for dictionaries (and 
perhaps sets). I guess the idea is that this generic code should 
be valid for any container which implements the in operator:

     if(a in r) writeln(r[a]);

On a different note, I do wish D had tuple literals like Python 
has.