Walter Bright wrote: > Jari-Matti Mäkelä wrote:
>> - bloat: Scala is more lightweight. I've heard Walter say that he doesn't >> like e.g. library defined control structures - > > Actually, you can do them with "lazy" function arguments. There was an > example somewhere of doing control structures with it. Agreed, you /can/ do something similar. But in Scala it's the standard way of doing things. If you compare the grammars of both languages, you'll see that Scala is a bit lighter than D (see http://www.scala- lang.org/sites/default/files/linuxsoft_archives/docu/files/ScalaReference.pdf) > >> it's double-edged sword, and >> D and Scala have taken different paths here (in D if something is >> commonly used and it can be made built-in, it will be added to the >> compiler, in Scala it's the opposite). > > That's not quite right. I'll add things to the core if there is a good > reason to - the compiler can do things a library cannot. For example, > string literals. I exaggerated a bit. But there are some constructs that some think should not be there, e.g. foreach_reverse. >> - bugs: IMHO the unspecified parts of D and the huge amount of bugs made >> it unusable for me. Luckily I found Scala and have been really happy with >> it. I've only found maybe 1-2 bugs in it during the last 1.5 years. I >> usually find about 5-10 bugs in DMD in 15 minutes after coming back to D. > > I couldn't find any bugs you've submitted to the D bugzilla. If you > don't submit them, they won't get fixed <g>. I've submitted couple of reports years ago and luckily some of them have already been fixed. Maybe the search is broken. >> And I'm >> also so happy to find that thanks to authors' knowledge of type systems >> (dependent types, HM, System F, etc.) Scala is a genius at inferring >> types. D doesn't really have a clue. > > Can you give an example? http://d.puremagic.com/issues/show_bug.cgi?id=3042 auto foo = [ 1, 2L ]; // typeof == int[2u] auto foo = [ 2L, 1 ]; // typeof == long[2u] auto foo = [ "a", "abcdefgh" ]; // typeof == char[1u][2u] in D1 auto foo = [ [], [1,2,3] ]; // doesn't even compile > >> Especially the array literal type inference is really naive. > > How should it be done? You shouldn't use the type of the first given element when constructing the type of the array. If you have [ e_1, ..., e_n ], the type of the literal is unify(type_of_e_1, ..., type_of_e_n) + "[]". For instance: => typeof([ [], [1,2,3] ]) => unify( typeof([]), typeof([1,2,3]) ) + "[]" => unify( "a[]", unify(typeof(1),typeof(2),typeof(3)) + "[]" ) + "[]" => unify( "a[]", unify("int","int","int") + "[]" ) + "[]" => unify( "a[]", "int" + "[]" ) + "[]" => unify( "a[]", "int[]" ) + "[]" // a is a local type var, subst = { a -> int } => "int[]" + "[]" => "int[][]"
