coro 1.1.0

• Iterator functions are now allowed to have a close argument. If they do, they will be called with a close = TRUE value when iteration is terminated early. This gives the opportunity to clean up resources.

• Generators now run on.exit() expressions when they are closed.

• Iterators managed by coro::loop() and by generator for loops are now cleaned up when terminated early, either because of an error or because of a break (#52).

• Implicit and explicit return values of generators are no longer yielded. This is consistent with Javascript and Python and simplifies certain idioms (#51).

• Generators and async functions assigned in namespaces no longer produce R CMD check notes about visible bindings (#40).

coro 1.0.5

• Async functions created by coro::async() now return their promises::promise() invisibly (#46, @shikokuchuo).

• Fixes for CRAN checks.

coro 1.0.4

• Internal fix for R-devel.

coro 1.0.3

• coro::as_iterator() method added for reticulate Python objects, enabling usage like: coro::loop(for (elem in my_py_object) ...) (#37, @t-kalinowski).

coro 1.0.2

• The exhaustion sentinel is now as.symbol(".__exhausted__.") instead of as.symbol("exhausted") to reduce the risk of collisions. It is also recommended to never store the exhaustion sentinel in an environment or list, and instead use it as a temporary value to further reduce the risk of collisions (#35).

• Fixed a leak that occurred via JIT caching (#36).

coro 1.0.1

• collect() now preserves lists and data frames (#32).

coro 1.0.0

This is the first public version of coro.

• Python iterators created with the reticulate package can now be composed with coro generators. They can also be used with loop() and collect().

• iterate() has been renamed to loop() to avoid name clash and semantic conflict with reticulate::iterate().

• collect() calls as_iterator() on its input.

• as_iterator() is now a generic function (#28).

• Generators and async functions now support on.exit() expressions. They also support exit expressions installed with functions like withr::local_options(). This requires R >= 3.5.

• Generator arguments are forced on reentry in the approriate context (e.g. in the tryCatch() context if generator was yielded from a tryCatch()). This makes it possible to clean up cancelled generators (by jumping from the generator with a restart) or propagate errors in async functions.

• Generators and async functions now support yielding within tryCatch() expressions.

• Generators and async functions are now disabled when an unexpected exit occurs (error, interrupt, restart invokation, debugger exit, etc.). Reentering the generator is an error.

• Generators and async functions now support stepping with browser(). Set options(coro_debug = TRUE) for browsing all functions created with coro. Use coro_debug() for browsing specific functions.

• generator() now accepts functions of one argument. The first time a generator is called the argument is defined in the suspendable function. On subsequent invokations, the argument is returned from yield().

• generator() now creates generator factories. It takes a function template and returns a function that creates generator functions from this template. This is consistent with languages like Javascript and Python.

• The async() function operator creates functions for cooperative concurrency using the later and promises framework.

  async_generator() creates iterable functions that are also awaitable.

• The iterator abstraction has been removed from coro. It is replaced with the following protocol:

  • An iterator is a function. You advance it and get a new value by calling it.
  • An iterator signals exhaustion by returning exhausted() (or equivalently, the quote(exhausted) symbol).

• Exhausted generators no longer throw when called again. Instead, they return the exhausted() sentinel (#6).

• Fixed top-level break statements in loops (#7).

coro 0.0.1

Initial release