RELEASE_NOTES.md

4.0.0-beta-56

• Add NotifyPropertyChanged for the HasErrors property.

4.0.0-beta-55

• Add TwoWayT bindings for workflows that reuse bindings.
• Add OneWayToSeqT bindings.
• Add vopt and opt bindings for OneWayT, OneWayToSourceT, and TwoWayT bindings.
• Add .NET 8 target and remove .NET Core 3.1 support

4.0.0-beta-54

• Added the Readme file to the generated nuspec file so that it shows up on nuget.org.
• Added some debug logs to the performance logger at the top level.
• Brought up new functions to parity with the performance logger.

4.0.0-beta-53

• Corrected the threaded dispatch case when an immediate UI update was needed. Done by adding an unschedule Dispatcher job at the same priority as the other scheduler jobs, which will force it to run in the correct order before any of the execute update jobs arrive to the queue, thus preventing any of the old scheduler jobs from getting executed after this immediate UI update.
• Added debug logging with counters to represent the increasing sequence of setUiState being called and scheduled on other threads (to ensure proper ordering).

4.0.0-beta-52

• Fixed a bug in the threaded dispatch case that could result in an out-of-date model being updated.
• Skip intermediate updates to view model when they queue up in the threaded case.
• Reverted the following change from beta-51 because Set caching is problematic:
  • Notify Property Changed directly on Set rather than waiting around for the next update. Set value is now cached until the next time update/dispatch is called.

4.0.0-beta-51

• Allow skipping intermediate updates when they pile up on UI Thread.
• Notify Property Changed directly on Set rather than waiting around for the next update. Set value is now cached until the next time update/dispatch is called.

4.0.0-beta-50

• Upgraded to Elmish v4
  • BREAKING: Changed syntax of WpfProgram.withSubscription to now take named list of Subscribe<'msg> = Dispatch<'msg> -> IDisposable (note the IDisposable return). This function now gets called every time 'model updates (previously it was only called on startup). This allows starting and stopping of subscriptions from this function by the given string list identifier.
  • BREAKING: Changed Sub<'msg> to Effect<'msg> everywhere (Effect<'msg> = Dispatch<'msg> -> unit, see difference with Subscribe<'msg> above). Also renames helper functions. This does not break Cmd<'msg>s that didn't name the Sub<'msg> type (or helpers).
  • Added WpfProgram.withTermination to allow conditional exit of the elmish loop on a specific 'msg, as well as specify a side effect on exit.
• Added more documentation throughout the helpers.
• Updated some of the sample projects for clarity.

4.0.0-beta-49

• Added Binding.SubModelT.seq that allows a seq of static sub models that are all properly updated when there is a dispatch.

4.0.0-beta-48

• Added ability to run elmish update loop on a background thread rather than only on the main UI thread.
• Added a Threading sample project demonstrating above feature.

4.0.0-beta-47

• Improved ViewModelBase to infer view model property types from the Model getter rather than needing to be explicitly specified.
• Added 't type parameter to Binding<'model, 'msg, 't> everywhere to support above feature. Binding<'model, 'msg> is defined as Binding<'model, 'msg, obj> for full backwards compatibility.
• Added Binding.boxT and Binding.unboxT to support moving back and forth between the two.
• Added Binding.OneWayT, Binding.OneWayToSourceT and Binding.CmdT modules for creating strongly typed primitives for the top feature.
• Added types internally to carry everything through (mostly provably) correctly.
• Added 'viewModel type parameter to WpfProgram<'model, 'msg, 'viewModel> to support using a static view model at the top level. WpfProgram<'model, 'msg> is defined as WpfProgram<'model, 'msg, obj> for full backwards compatibility. Also made WpfProgram core type more generic, replacing the list of bindings with equivalent but more flexible CreateViewModel and UpdateViewModel functions.
• Added WpfProgram.mkSimpleT, WpfProgram.mkProgramT and WpfProgram.mkProgramWithCmdMsgT for making programs that use static view models as the top-level data context.
• Modified SubModelStatic sample project to use new static view model features.

4.0.0-beta-46

• Added ViewModelBase which allows view models to be defined as static types with real properties rather than unnamed dynamic types with stringly named properties.
• Added Binding.SubModelT, Binding.SubModelSeqUnkeyedT, Binding.SubModelSeqKeyedT and Binding.SubModelWinT modules for creating these static types as sub models.
• Replaced internal usage of refs in dynamic view model with get/set functions to allow for matting of the type.
• Added some internal types to support ViewModelBase.
• Improved documentation.
• Added a SubModelStatic sample project using above feature.

4.0.0-beta-45

• Improved performance of Lazy effect by reducing calls to later model mappings
• Removed SourceOrTarget and DuplicateIdException from public API (added in 4.0.0-beta-42)
• Improved caching effect to not invalidating the cache too early (an issue introduced in version 3.5.3 via PR 181)
• Renamed Binding.SetMsgWithModel to Binding.setMsgWithModel (breaking public API added in 4.0.0-beta-42)
• Fixed bug with mapMsgWithModel and setMsgWithModel where the original model was sometimes given (an issue introduced in 4.0.0-beta-42)
• Replaced framework targets net461 and net5.0-windows with net480 and net6.0-windows respectively.
• Updated minimum FSharp.Core version to 6.0.5.
• Updated minimum Microsoft.Extensions.Logging.Abstractions version to 6.0.1.
• Fixed broken log statement called when a SubModelSelectedItem binding can't find an item in a SubModelSeq binding.

4.0.0-beta-44

• Fixed sticky effect that was broken in 4.0.0-beta-42

4.0.0-beta-43

• Added WpfProgram.withElmishErrorHandler
• Improved debugging experience by overriding GetDynamicMemberNames
• Relaxed version constrains on FSharp.Core and Microsoft.Extensions.Logging.Abstractions

4.0.0-beta-42

• Improved API of WindowState<_>
• Dropped support for .NET Core 3.0. Still have support for .NET Core 3.1.
• Added setMsg in the Binding module
• Added setMsgWithModel in the Binding module
• Removed id in the Binding module (that was added in 4.0.0-beta-3)
• Lazy effect now exposed via the name addLazy
• Validation effect now exposed via the name addValidation
• Sticky effect now exposed via the name addSticky
• Added caching effect via the name addCaching
• Now logging when WPF tries to get or set a binding and an exception is thrown
• Added to the SubModelSeq method API an overload that only takes bindings
• Added support for a SubModelSeq variant that does involve IDs
• SubModelSeq variant that involves IDs will now merge elements without considering IDs if duplicate IDs are detected
• Fixed bug (present in 3.5.8) where ArgumentNullException is thrown from INotifyDataErrorInfo.GetErrors when given null
• Now logging and returning false to WPF if selection in a SubModelSelectedItem binding fails
• Added prebuilt bindings for Selector.SelectedIndex
• Added Binding.TwoWay.id to API
• Removed trace logging during a successful set in a SubModelSelectedItem binding
• Added one-way-to-source binding
• Added function-based API for for one-way bindings
• Added composable monomorphic dispatch wrapping
• Switched the order of inputs in the function given to Binding.mapMsgWithModel. This is breaking for public API introduced in 4.0.0-beta-1.
• Added alterMsgStream to API. This feature is a replacement for what was previously called wrapDispatch.

4.0.0-beta-41

• Fixed "backwards typing" (#373) and other bugs (like #371) introduced in 4.0.0-beta-40 with more careful use of the Dispatcher (#374)

4.0.0-beta-40

• Removed recently added trace logging of INotifyDataErrorInfo.HasErrors (#354)
• Fixed typos in documentation and logging (#357)
• Fixed race condition with Dispatcher (#359)
• Removed overload of ViewModel<_,_>.ToString because of slow performance (#370)

4.0.0-beta-3

• Added support for composable binding stickiness sticky
• Added support for composable binding validation withValidation
• Added support for composable binding laziness via lazy'
• Improved logging
• Changed CurrentModel and UpdateModel on ViewModel<,> from public to internal
• runWindow now shows the given window after settings its DataContext. This removes the need to have Visibility values default to Collapsed.
• Changed minimum Elmish version from 3.0.3 to 3.1.0 (which is currently the latest). Commands created with OfAsync are now executed on a threadpool thread. For example, it is now easier to show file dialogs without blocking the Elmish dispatch loop. See this diff.

4.0.0-beta-2

• Added logging when INotifyDataErrorInfo.HasErrors is called
• Fixed bug in INotifyDataErrorInfo.HasErrors where true always returned after true first correctly returned

4.0.0-beta-1

• Breaking: Removed the obsolete binding functions in the BindingFn module
• Breaking: Removed the obsolete function Elmish.WPF.Cmd.showWindow
• Breaking: Removed all occurrences of the argument wrapDispatch from the methods used to create a binding. There is currently no migration path. Please create an issue if this is a negative impact for you.
• Breaking: App initialization is now done using the WpfProgram module instead of the Program module
• Breaking: Removed ElmConfig. For controlling logging, see below. For specifying a binding performance log threshold (corresponding to the old ElmConfig.MeasureLimitMs field), use WpfProgram.withBindingPerformanceLogThreshold
• Breaking: The method Binding.oneWaySeq is implemented by calling the method Binding.oneWaySeqLazy with equals = refEq and map = id. This is a breaking change when using a mutable data structure for the sequence. Compensate by directly calling Binding.oneWaySeqLazy with equals = fun _ _ = false.
• Breaking: Some calls to Binding methods now include an equality constraint. This only is only breaking if the corresponding type included the NoEquality attribute.
• Added binding mapping functions
  • Added mapModel, mapMsg, and mapMsgWithModel in both the Binding and Bindings modules
  • These functions enable common model and message mapping logic to be extracted
  • See the SubModelSeq sample for an excellent use of mapModel and mapMsg
• Improved logging:
  • Now uses Microsoft.Extensions.Logging for wide compatibility and easy integration into common log frameworks
  • Use WpfProgram.WithLogger to pass an ILoggerFactory for your chosen log framework
  • Can control specific log categories
  • See the samples for a demonstration using Serilog

3.5.8

• Removed overload of ViewModel<_,_>.ToString because of slow performance (#370)

3.5.7

• Excluded 4.* prereleases from possibilities for version of Elmish dependency
• Added support for multiple validation errors
• Added target net5.0-windows
• ViewModel<'model, 'msg> now overrides object.ToString() and returns a string representation of the current 'model instance. This is only intended for debugging. No guarantees are given about the exact structure of the returned string.
• Fixed incorrect spelling of a word in a log message

3.5.6

• The amount of time used to update OneWaySeq and SubModelSeq bindings has been significantly decreased. This includes all cases of a SubModelSeq binding and all cases of a OneWaySeq binding for which equals returns false.

3.5.5

• Fix exception when showing sub-windows as part of init

3.5.4

• Windows may now be created on any thread

3.5.3

• Fix crash when init returns a command opening a subModelWin

3.5.2

• Improved error handling when collection bindings contain duplicates

3.5.1

• Improve performance of Binding.oneWaySeq, Binding.oneWaySeqLazy, and Binding.subModelSeq

3.5.0

• Add netcoreapp3.0 target

3.4.1

• Corrected type parameter of getId in oneWaySeqLazy

3.4.0

• Make model/dispatch available to getWindow in Binding.subModelWin

3.3.0

• Added optional dispatch wrapper to two-way bindings and command bindings, which allows dispatches to be throttled/debounced etc.

3.2.1

• Fixed ElmConfig.MeasureLimitMs not being used

3.2.0

• Added proper dialog/window support using Binding.subModelWin. See the readme for more and the NewWindow sample for an example.
• Deprecated Cmd.showWindow (use Binding.subModelWin instead)

3.1.0

• Added Program.withDebugTrace which is similar to withConsoleTrace but writes using System.Diagnostics.Debug.WriteLine (e.g. to the VS output window)

3.0.0

• The most massive (and hopefully useful) update yet!
• Breaking: Overload-based syntax for Binding. The old Binding module is deprecated and renamed to BindingFn. The new Binding is a static class with static methods, providing many overloads for flexibility. To migrate, replace all occurrences of Binding. with BindingFn. and follow the deprecation warnings.
• Breaking: The Elmish.WPF.Internal namespace has been removed and everything in it that should actually be internal has been marked internal. This includes ViewModel.
• Breaking: Elmish.WPF.Internal.BindingSpec<_,_> has been moved/renamed to Elmish.WPF.Binding<_,_>. It should thus be more pleasant to use in type annotations.
• Breaking: Elmish.WPF.Utilities.ViewModel.designInstance has been moved to Elmish.WPF.ViewModel. Furthermore, it returns obj since ViewModel is internal.
• Breaking: Removed twoWayIfValid. It hasn’t worked for a while due to core Elmish internals, and was of suspect utility anyway.
• New: Many more helpful Binding signatures available due to the new overload-based syntax.
• New: More general Binding.subModel and Binding.subModelSeq overloads that allow a more idiomatic Elm architecture even with static views. For background information, see #86 (the issue is otherwise outdated).
• New: Sticky subModelOpt bindings that returns the last non-null model when model is None (useful when animating out stuff)
• New: elmEq and refEq as useful equality defaults for lazy bindings. elmEq efficiently uses reflection to do a comparison for each member that is referential for reference types except strings, and structural for strings and value types.
• New: Program.mkSimpleWpf and Program.mkProgramWpf with more WPF-friendly signatures.
• New: Program.mkProgramWpfWithCmdMsg for easily following the CmdMsg pattern to allow testable commands. See the FAQ in the readme for details.
• New: Cmd.showWindow helper to open a new window.
• New: Slow calls can be logged (configurable threshold).
• New: Made available Program.startElmishLoop which is a low-level function that starts an Elmish loop given an Elmish Program and a WPF FrameworkElement. You probably won’t need it.
• Improvement: Logs now indicate the binding path.
• Improvement: Possibly better performance due to internals now using ValueOption instead of Option.
• Improvement: Finally added (lots of) unit tests, so confidence of correct functionality is higher. (No critical bugs were found when creating the tests.)

2.0.0

• No changes, but updated for Elmish 3.0 so the package can finally move out of beta

2.0.0-beta-11

• Add Binding.subModelSelectedItem

2.0.0-beta-10

• Fix checkboxes erroneously being shown as failing validation (#78) by @BillHally
• The above fix also fixes binding warnings for two-way bindings

2.0.0-beta-9

• Add new bindings oneWayOpt and twoWayOpt (#75)
• Update to Elmish 3.0.0-beta-7

2.0.0-beta-8

• Add new binding subBindingSeq, see readme for details.

2.0.0-beta-7

• Fix Elmish dependency version in nuget spec

2.0.0-beta-6

• Update to Elmish 3
• Dispatch on UI thread to block instead of getting weird UI behaviour from race conditions when updates take too long

2.0.0-beta-5

• Fix subModelSeq items being unselected during updates

2.0.0-beta-4

• Breaking: Change order of oneWayLazyWith arguments to and rename it to oneWayLazy, removing the existing oneWayLazy function. The rationale is explained in #60 . To migrate from 2.0.0-beta-3 to 2.0.0-beta-4: Add (=) as the equals parameter to oneWayLazy usages, and rename oneWayLazyWith usages to oneWayLazy.
• Add Binding.oneWaySeqLazy

2.0.0-beta-3

• Add convenience function to create design-time VMs

2.0.0-beta-2

• Improve log messages

2.0.0-beta-1

• Complete rewrite, several breaking changes and new features
• twoWayValidation is called twoWayIfValid (because that’s what it is, and it clearly separates it from the new twoWayValidate)
• oneWayMap is called oneWayLazy (its implementation has changed, and the use case has expanded, but is similar)
• cmd and cmdIf have been renamed paramCmd and paramCmdIf, because the old names have new signatures/use-cases
• model has been renamed subModel because it’s more clear, and consistent with the new subModelOpt and subModelSeq
• Program.runDebugWindow has been removed in favour of Program.runWindowWithConfig
• Bundled Elmish has been removed, and Elmish 2.0 is used as an external dependency
• Any Application instance instantiated before calling Program.run... will now be used
• Several new functions in the Binding module; dot into it in your IDE or see the repository for samples or source code

1.0.0-beta-7

• Fix for #19, model to view updates for validation bindings

1.0.0-beta-6

• Implemented INotifyDataErrorInfo and corresponding bindings
• Added some documentation for binding assemblers
• Added message box error handler to Program module

1.0.0-beta-5

• Target F# 4.1
• Latest fable-elmish, includes memory leak fix

1.0.0-beta-4

• Added Program.withExceptionHandler

1.0.0-beta-3

• Fixing nuget framework version

1.0.0-beta-2

• Added command parameter
• Renamed Binding.vm to Binding.model
• Reorganized samples and added performance sample (WIP)

1.0.0-beta-1

• Fixing two way binding bugs

0.9.0-beta-9

• Elmish all the WPF!