diff --git a/pkgs/plt-services/meta/announcements/v6.0.1.txt b/pkgs/plt-services/meta/announcements/v6.0.1.txt new file mode 100644 index 0000000000..897bc08d45 --- /dev/null +++ b/pkgs/plt-services/meta/announcements/v6.0.1.txt @@ -0,0 +1,62 @@ +1399579520 +Racket v6.0.1 + +* A new `racket/undefined` library exports `undefined` as the value + currently produced by + + (letrec ([x x]) x) + + This library anticipates a future where that expression will raise + an exception. The `racket/undefined` library will continue to offer + the `undefined` value as a bridge between versions and as a last + resort. + +* The drawing and GUI libraries provide improved support for + high-resolution bitmaps and their use on Retina displays. For + example, `read-bitmap` includes a `#:try-@2x?` option to trigger + substitutions through the usual "@2x" naming convention. + +* Check Syntax cooperates with Typed Racket to show arrows and other + Check Syntax highlighting even when there is a type error. + +* Functions provided via contract-out that have first-order contracts + perform better. + +* The contract boundary between typed/untyped modules is much less + expensive. Typed Racket now avoids generating contracts for places + where contracts failures cannot happen. + +* Occurrence typing now works better with when/unless. Example: + + (let ((x (read))) + (unless (number? x) (error 'bad-input)) + (add1 x)) + +* Types in Typed Racket are now pretty-printed. + +* Function types can now be written in prefix style, which is now + preferred and is used for printing. Infix function types are still + accepted for backwards compatibility. + +* A new `->*' type constructor is used for writing types for functions + with optional and keyword arguments. The notation is similar to the + matching contract combinator. + +* Typed Racket forms do not have a `:' suffix by default now. For + example, the `struct' form replaces `struct:'. The suffixed versions + are all provided for backwards compatibility. + +* Typed Racket now has preliminary support for classes and + objects. However, it is still experimental and the APIs are subject + to change. + +* Type aliases in Typed Racket now support recursion and mutual + recursion. For example, `(define-type (MyList X) (U Null (Pair X + (MyList X))))' is now a valid type alias. + +* Plot correctly renders intersecting 3D graphs and non-grid-aligned + 3D rectangles. + +* Elements in plots output in PDF/PS format have the same relative + scale as in other formats. In particular, it is not necessary to + adjust `plot-font-size` to make PDF plots look the same as PNG.