The F# Path to Relaxation
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The document discusses the F# programming language, emphasizing its open, cross-platform nature and active community contributions. It highlights various tools and libraries available for F#, including support for mobile and web applications, and presents examples of functional programming concepts and patterns in F#. Additionally, it showcases testimonials on the language's reliability and effectiveness in real-world applications.
![/// The view function giving updated content for the page
let view model dispatch =
match model.Text with
| [| |] ->
div [] [ div [] [str "Loading..."] ]
| _ ->
div [ ClassName "container" ] [
button [ OnClick (fun _ -> dispatch Faster) ] [ str "Faster" ]
div [ ClassName "theText" ] [ str model.Text.[model.Index] ]
button [ OnClick (fun _ -> dispatch Slower) ] [ str "Slower" ]
div [] [ str (sprintf "Ticks Per Update: %d" model.TicksPerUpdate) ]
]
A functional-reactive
dynamic web view](https://image.slidesharecdn.com/donsyme-fsharp-relaxation-given-180604082507/85/The-F-Path-to-Relaxation-32-320.jpg)
The F# Path to Relaxation
- 1. | Basel The F# Path to Relaxation Language Design, Platforms, Community, Openness Don Syme, F# Community Contributor, MSR Principal Researcher in Mobile Tools
- 6. X Y
- 11. X Y
- 13. F# is open, cross- platform, neutral, independent All F# language and tooling is accepting contributions The F# community is very “self-empowered” fsharp.org Xamarin provide F# tools Android and iOS The Visual F# Tools are Microsoft’s professional tools for Windows and Azure Debian, RPM and .NET Core for Linux/OSX The F# Compiler Service powers many other tools Fable for F#-to- Javascript SAFE for F# fullstack F# 4.1 now complete!
- 15. fsharp.github.io
- 21. fable.io
- 26. let symbolUses = symbolUses |> Array.filter (fun symbolUse -> …) |> Array.Parallel.map (fun symbolUse -> …) |> Array.filter (fun … -> …) |> Array.groupBy (fun … -> …) |> Array.map (fun … ->….)
- 28. https://lukemerrett.com/fsharp-domain-modelling/ type Status = | Online | Unresponsive of string | Missing of string | NotChecked of string | Ignored
- 29. https://medium.com/@odytrice Ody Mbegbu type Value = | Integer of int64 | String of string | Date of DateTime | Data of string | Bool of bool | Dict of (string * Value) list | Array of Value list
- 32. /// The view function giving updated content for the page let view model dispatch = match model.Text with | [| |] -> div [] [ div [] [str "Loading..."] ] | _ -> div [ ClassName "container" ] [ button [ OnClick (fun _ -> dispatch Faster) ] [ str "Faster" ] div [ ClassName "theText" ] [ str model.Text.[model.Index] ] button [ OnClick (fun _ -> dispatch Slower) ] [ str "Slower" ] div [] [ str (sprintf "Ticks Per Update: %d" model.TicksPerUpdate) ] ] A functional-reactive dynamic web view
- 33. /// The view function giving updated content for the page let view (model: Model) dispatch = if model.Pressed then Xaml.Label(text="I was pressed!") else Xaml.Button(text="Press Me!", command=(fun () -> dispatch Pressed)) A functional-reactive mobile app view
- 34. type Msg = | Pressed type Model = { Pressed: bool } let init() = { Pressed=false } let update msg model = match msg with | Pressed -> { model with Pressed = true } let view (model: Model) dispatch = if model.Pressed then Xaml.abel(text="I was pressed!") else Xaml.Button(text="Press Me!", command=(fun () -> dispatch Pressed)) type App () = inherit Application () do Program.run init update view A full Xamarin mobile app The messages The initial model The update function The dynamic view Host+run github.com/fsprojects/Elmish.XamarinForms/ The model
- 37. X Y
- 40. type Vector2D (dx:double, dy:double) = let d2 = dx*dx+dy*dy member v.DX = dx member v.DY = dy member v.Length = sqrt d2 member v.Scale(k) = Vector2D (dx*k, dy*k) Inputs to object construction Exported properties Exported method Object internals
- 41. Object Interface Types type IObject = interface ISimpleObject abstract Prop1 : type abstract Meth2 : type -> type Object Expressions { new IObject with member x.Prop1 = expr member x.Meth1 args = expr } { new Object() with member x.Prop1 = expr interface IObject with member x.Meth1 args = expr interface IWidget with member x.Meth1 args = expr } Constructed Class Types type ObjectType(args) = let internalValue = expr let internalFunction args = expr let mutable internalState = expr member x.Prop1 = expr member x.Meth2 args = expr
- 44. objects as a single paradigm overuse of hierarchical classification large abstractions many holes failure points declarations expressions complex inheriting complex
- 48. 350,000 lines of C# OO by offshore team 30,000 lines of robust F#, with parallel +more features An application to evaluate the revenue due from Balancing Services contracts in the UK energy industry http://simontcousins.azurewebsites.net/does-the-language-you-use-make-a- difference-revisited/
- 51. Zero bugs in deployed system “F# is the safe choice for this project, any other choice is too risky” An application to evaluate the revenue due from Balancing Services contracts in the UK energy industry http://simontcousins.azurewebsites.net/does-the-language-you-use-make-a- difference-revisited/
- 53. X Y
- 59. module BasicPatterns = let (|Value|_|) (e:FSharpExpr) = ... let (|Const|_|) (e:FSharpExpr) = ... let (|TypeLambda|_|) (e:FSharpExpr) = ... let (|Lambda|_|) (e:FSharpExpr) = ... let (|Application|_|) (e:FSharpExpr) = ... let (|IfThenElse|_|) (e:FSharpExpr) = ... let (|Let|_|) (e:FSharpExpr) = ... let (|LetRec|_|) (e:FSharpExpr) = ... let (|NewRecord|_|) (e:FSharpExpr) = ... let (|NewUnionCase|_|) (e:FSharpExpr) = ... let (|NewTuple|_|) (e:FSharpExpr) = ... let (|TupleGet|_|) (e:FSharpExpr) = ...
- 60. let (|IdentifierNameSyntax|_|) (n: CSharpSyntaxNode) = match n with | :? IdentifierNameSyntax as t -> Some(t.CSharpKind(), t.Identifier) | _ -> None let (|IdentifierName|_|) (n: CSharpSyntaxNode) = match n.CSharpKind() with | SyntaxKind.IdentifierName -> ... | _ -> None let (|QualifiedNameSyntax|_|) (n: CSharpSyntaxNode) = match n with | :? QualifiedNameSyntax as t -> ... | _ -> None let (|QualifiedName|_|) (n: CSharpSyntaxNode) = match n.CSharpKind() with | SyntaxKind.QualifiedName -> ... | _ -> None
- 62. Code Data
- 64. 1 2 3 4 5 6 7 2012 2013 6,432 10,537
- 66. Statically Typed Dynamically Typed Options • make statically typed langs more dynamic • make dynamically typed langs more static • apply moderated static typing much more broadly
- 70. 01/06/2018 70
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- 80. integrating internet-scale information services directly into the program's variable and type space is probably the most innovative programming language idea I’ve heard of in a decade
- 81. ✔ ✔ Code Data
- 82. X Y
- 83. Sync Async
- 86. Synthesis from contradiction is at the heart of applied PL design Opposites come in all shapes and flavours Achieve relaxation today ☺ Code Data Functi onal Objec ts Open Enter prise Sync Async … …