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| -rw-r--r-- | web/news.txt | 69 |
1 files changed, 64 insertions, 5 deletions
diff --git a/web/news.txt b/web/news.txt index db233cc71..dfeec45e6 100644 --- a/web/news.txt +++ b/web/news.txt @@ -3,27 +3,86 @@ News ==== .. - 2015-11-XX Version 0.12.2 released + 2016-01-XX Version 0.13.0 released ================================== - This is a bugfix release. - + This release implements no new features. Instead existing features have + been fleshed out as we're heading to version 1. Changes affecting backwards compatibility ----------------------------------------- - ``macros.newLit`` for ``bool`` now produces false/true symbols which actually work with the bool datatype. - - when compiling to JS, ``Node``, ``NodeType`` and ``Document`` are no longer + - When compiling to JS, ``Node``, ``NodeType`` and ``Document`` are no longer defined. Use the types defined in ``dom.nim`` instead. - The check ``x is iterator`` (used for instance in concepts) was always a weird special case (you could not use ``x is proc``) and was removed from the language. - - Implicit return type for iterators have been removed from the language. - Top level routines cannot have the calling convention ``closure`` anymore. + Syntax changes + ~~~~~~~~~~~~~~ + + The parser now considers leading whitespace in front of operators + to determine if an operator is used in prefix or infix position. + This means that finally ``echo $foo`` is parsed as people expect + which is as ``echo($foo)``. It used to be parsed as ``(echo) $ (foo)``. + + ``echo $ foo`` continues to be parsed as ``(echo) $ (foo)``. + + + Iterator changes + ~~~~~~~~~~~~~~~~ + + Implicit return type inference for iterators has been removed from the language. The following used to work: + + .. code-block:: nim + iterator it = + yield 7 + + This was a strange special case and has been removed. Now you need to write it like so which is consistent with procs: + + .. code-block:: nim + iterator it: auto = + yield 7 + + + Closure changes + ~~~~~~~~~~~~~~~ + + The semantics of closures changed: Capturing variables that are in loops do not produce a new environment. Nim closures behave like JavaScript closures now. + + The following used to work as the environment creation used to be attached to the loop body: + + .. code-block:: nim + + proc outer = + var s: seq[proc(): int {.closure.}] = @[] + for i in 0 ..< 30: + let ii = i + s.add(proc(): string = return ii*ii)) + + This behaviour has changed in 0.13.0 and now needs to be written as: + .. code-block:: nim + + proc outer = + var s: seq[proc(): int {.closure.}] = @[] + for i in 0 ..< 30: + (proc () = + let ii = i + s.add(proc(): int = return ii*ii))() + + The reason is that environment creations are now only performed once + per proc call. This change is subtle and unfortunate, but: + + 1. Affects almost no code out there. + 2. Is easier to implement and we are at a point in Nim's development process where simple+stable wins over perfect-in-theory+unstable-in-practice. + 3. Implies programmers are more in control of where memory is allocated which is benefitical for a systems programming language. + + 2015-10-27 Version 0.12.0 released ================================== |