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Merge pull request #1924 from nyanfly/master

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Make whitespace more consistent
This commit is contained in:
Adam Bard 2015-10-31 18:21:21 +08:00
commit 2202c4c6d6
1 changed files with 37 additions and 37 deletions
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fsharp.html.markdown
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@ -31,14 +31,14 @@ If you want to try out the code below, you can go to [tryfsharp.org](http://www.
// The "let" keyword defines an (immutable) value
let myInt = 5
let myFloat = 3.14
let myString = "hello" //note that no types needed
let myString = "hello" // note that no types needed
// ------ Lists ------
let twoToFive = [2;3;4;5] // Square brackets create a list with
let twoToFive = [2; 3; 4; 5] // Square brackets create a list with
// semicolon delimiters.
let oneToFive = 1 :: twoToFive // :: creates list with new 1st element
// The result is [1;2;3;4;5]
let zeroToFive = [0;1] @ twoToFive // @ concats two lists
// The result is [1; 2; 3; 4; 5]
let zeroToFive = [0; 1] @ twoToFive // @ concats two lists
// IMPORTANT: commas are never used as delimiters, only semicolons!
@ -53,7 +53,7 @@ add 2 3 // Now run the function.
// to define a multiline function, just use indents. No semicolons needed.
let evens list =
let isEven x = x%2 = 0 // Define "isEven" as a sub function
let isEven x = x % 2 = 0 // Define "isEven" as a sub function
List.filter isEven list // List.filter is a library function
// with two parameters: a boolean function
// and a list to work on
@ -75,7 +75,7 @@ let sumOfSquaresTo100piped =
// you can define lambdas (anonymous functions) using the "fun" keyword
let sumOfSquaresTo100withFun =
[1..100] |> List.map (fun x -> x*x) |> List.sum
[1..100] |> List.map (fun x -> x * x) |> List.sum
// In F# there is no "return" keyword. A function always
// returns the value of the last expression used.
@ -109,7 +109,7 @@ optionPatternMatch invalidValue
// The printf/printfn functions are similar to the
// Console.Write/WriteLine functions in C#.
printfn "Printing an int %i, a float %f, a bool %b" 1 2.0 true
printfn "A string %s, and something generic %A" "hello" [1;2;3;4]
printfn "A string %s, and something generic %A" "hello" [1; 2; 3; 4]
// There are also sprintf/sprintfn functions for formatting data
// into a string, similar to String.Format in C#.
@ -131,19 +131,19 @@ module FunctionExamples =
// basic usage of a function
let a = add 1 2
printfn "1+2 = %i" a
printfn "1 + 2 = %i" a
// partial application to "bake in" parameters
let add42 = add 42
let b = add42 1
printfn "42+1 = %i" b
printfn "42 + 1 = %i" b
// composition to combine functions
let add1 = add 1
let add2 = add 2
let add3 = add1 >> add2
let c = add3 7
printfn "3+7 = %i" c
printfn "3 + 7 = %i" c
// higher order functions
[1..10] |> List.map add3 |> printfn "new list is %A"
@ -151,7 +151,7 @@ module FunctionExamples =
// lists of functions, and more
let add6 = [add1; add2; add3] |> List.reduce (>>)
let d = add6 7
printfn "1+2+3+7 = %i" d
printfn "1 + 2 + 3 + 7 = %i" d
// ================================================
// Lists and collection
@ -168,12 +168,12 @@ module FunctionExamples =
module ListExamples =
// lists use square brackets
let list1 = ["a";"b"]
let list1 = ["a"; "b"]
let list2 = "c" :: list1 // :: is prepending
let list3 = list1 @ list2 // @ is concat
// list comprehensions (aka generators)
let squares = [for i in 1..10 do yield i*i]
let squares = [for i in 1..10 do yield i * i]
// prime number generator
let rec sieve = function
@ -190,8 +190,8 @@ module ListExamples =
| [first; second] -> printfn "list is %A and %A" first second
| _ -> printfn "the list has more than two elements"
listMatcher [1;2;3;4]
listMatcher [1;2]
listMatcher [1; 2; 3; 4]
listMatcher [1; 2]
listMatcher [1]
listMatcher []
@ -219,7 +219,7 @@ module ListExamples =
module ArrayExamples =
// arrays use square brackets with bar
let array1 = [| "a";"b" |]
let array1 = [| "a"; "b" |]
let first = array1.[0] // indexed access using dot
// pattern matching for arrays is same as for lists
@ -230,13 +230,13 @@ module ArrayExamples =
| [| first; second |] -> printfn "array is %A and %A" first second
| _ -> printfn "the array has more than two elements"
arrayMatcher [| 1;2;3;4 |]
arrayMatcher [| 1; 2; 3; 4 |]
// Standard library functions just as for List
[| 1..10 |]
|> Array.map (fun i -> i+3)
|> Array.filter (fun i -> i%2 = 0)
|> Array.map (fun i -> i + 3)
|> Array.filter (fun i -> i % 2 = 0)
|> Array.iter (printfn "value is %i. ")
@ -255,7 +255,7 @@ module SequenceExamples =
yield! [5..10]
yield! seq {
for i in 1..10 do
if i%2 = 0 then yield i }}
if i % 2 = 0 then yield i }}
// test
strange |> Seq.toList
@ -280,11 +280,11 @@ module DataTypeExamples =
// Tuples are quick 'n easy anonymous types
// -- Use a comma to create a tuple
let twoTuple = 1,2
let threeTuple = "a",2,true
let twoTuple = 1, 2
let threeTuple = "a", 2, true
// Pattern match to unpack
let x,y = twoTuple //sets x=1 y=2
let x, y = twoTuple // sets x = 1, y = 2
// ------------------------------------
// Record types have named fields
@ -297,7 +297,7 @@ module DataTypeExamples =
let person1 = {First="John"; Last="Doe"}
// Pattern match to unpack
let {First=first} = person1 //sets first="John"
let {First = first} = person1 // sets first="John"
// ------------------------------------
// Union types (aka variants) have a set of choices
@ -331,7 +331,7 @@ module DataTypeExamples =
| Worker of Person
| Manager of Employee list
let jdoe = {First="John";Last="Doe"}
let jdoe = {First="John"; Last="Doe"}
let worker = Worker jdoe
// ------------------------------------
@ -383,8 +383,8 @@ module DataTypeExamples =
type Rank = Two | Three | Four | Five | Six | Seven | Eight
| Nine | Ten | Jack | Queen | King | Ace
let hand = [ Club,Ace; Heart,Three; Heart,Ace;
Spade,Jack; Diamond,Two; Diamond,Ace ]
let hand = [ Club, Ace; Heart, Three; Heart, Ace;
Spade, Jack; Diamond, Two; Diamond, Ace ]
// sorting
List.sort hand |> printfn "sorted hand is (low to high) %A"
@ -419,7 +419,7 @@ module ActivePatternExamples =
| _ -> printfn "%c is something else" ch
// print a list
['a';'b';'1';' ';'-';'c'] |> List.iter printChar
['a'; 'b'; '1'; ' '; '-'; 'c'] |> List.iter printChar
// -----------------------------------
// FizzBuzz using active patterns
@ -479,7 +479,7 @@ module AlgorithmExamples =
List.concat [smallerElements; [firstElem]; largerElements]
// test
sort [1;5;23;18;9;1;3] |> printfn "Sorted = %A"
sort [1; 5; 23; 18; 9; 1; 3] |> printfn "Sorted = %A"
// ================================================
// Asynchronous Code
@ -536,7 +536,7 @@ module NetCompatibilityExamples =
// ------- work with existing library functions -------
let (i1success,i1) = System.Int32.TryParse("123");
let (i1success, i1) = System.Int32.TryParse("123");
if i1success then printfn "parsed as %i" i1 else printfn "parse failed"
// ------- Implement interfaces on the fly! -------
@ -570,12 +570,12 @@ module NetCompatibilityExamples =
// abstract base class with virtual methods
[<AbstractClass>]
type Shape() =
//readonly properties
// readonly properties
abstract member Width : int with get
abstract member Height : int with get
//non-virtual method
// non-virtual method
member this.BoundingArea = this.Height * this.Width
//virtual method with base implementation
// virtual method with base implementation
abstract member Print : unit -> unit
default this.Print () = printfn "I'm a shape"
@ -586,19 +586,19 @@ module NetCompatibilityExamples =
override this.Height = y
override this.Print () = printfn "I'm a Rectangle"
//test
let r = Rectangle(2,3)
// test
let r = Rectangle(2, 3)
printfn "The width is %i" r.Width
printfn "The area is %i" r.BoundingArea
r.Print()
// ------- extension methods -------
//Just as in C#, F# can extend existing classes with extension methods.
// Just as in C#, F# can extend existing classes with extension methods.
type System.String with
member this.StartsWithA = this.StartsWith "A"
//test
// test
let s = "Alice"
printfn "'%s' starts with an 'A' = %A" s s.StartsWithA