open System
let decorateSequence concatnator xs mapper decorator =
xs
|> List.map mapper
|> List.fold concatnator ""
|> decorator
let decorateAttributes xs mapper decorator =
decorateSequence (fun x y -> x + " " + y) xs mapper decorator
let decorateNodes xs mapper decorator =
decorateSequence (fun x y -> x + y) xs mapper decorator
let decorateNode (tag : string) s =
tag + s + (tag.Replace ("<", "</"))
type MetaNode =
HttpEquiv of string | Content of string
let markupMetaNode = function
| HttpEquiv s -> "Http-Equiv=\"" + s + "\""
| Content s -> "Content=\"" + s + "\""
type HeaderNode =
Meta of (MetaNode list) | Title of string
let markupHeaderNode = function
| Meta mls -> decorateAttributes mls markupMetaNode <| fun s -> "<meta" + s + " />"
| Title s -> decorateNode "<title>" s
type Header =
Head of (HeaderNode list)
let markupHeader = function
| Head hls -> decorateNodes hls markupHeaderNode <| decorateNode "<head>"
type BodyNode =
| Div of (BodyNode list)
| Span of (BodyNode list)
| P of (BodyNode list)
| Text of string
| H1 of string | H2 of string | H3 of string
| Br | Hr
let rec markupBodyNode = function
| Br -> "<br />"
| Hr -> "<hr>"
| H1 s -> decorateNode "<h1>" s
| H2 s -> decorateNode "<h2>" s
| H3 s -> decorateNode "<h3>" s
| Text s -> s
| Div bls -> decorateNodes bls markupBodyNode <| decorateNode "<div>"
| Span bls -> decorateNodes bls markupBodyNode <| decorateNode "<span>"
| P bls -> decorateNodes bls markupBodyNode <| decorateNode "<p>"
type Body =
Body of (BodyNode list)
let markupBody = function
| Body bls -> decorateNodes bls markupBodyNode <| decorateNode "<body>"
type HtmlNode =
Html of Header * Body
let markupHtmlNode = function
| Html (h, b) -> (markupHeader h) + (markupBody b)
|> decorateNode "<html>"
type DocType = DocType of string
let markupDocType = function
| DocType s -> "<!DOCTYPE " + s + ">"
type HtmlFile =
HtmlFile of (DocType * HtmlNode)
let markupHtmlFile = function
| HtmlFile (d, h) -> (markupDocType d) + (markupHtmlNode h)
HtmlFile (
DocType ("html"),
Html (
Head (
[Meta ([HttpEquiv ("Content-Type"); Content ("text/html; charset='utf-8'")]);
Title ("Html File")]
),
Body (
[H1 ("This"); H2 ("is"); H3 ("it");
Hr;
Div (
[Span ([Text ("a span node")]); P ([Text ("a paragraph")]); Br;
Text ("plain text")]
)]
)
)
) |> markupHtmlFile |> printfn "%s"
// You will see like below:
// <!DOCTYPE html><html><head><meta Http-Equiv="Content-Type" Content="text/html; c
// harset='utf-8'" /><title>HtmlBuilder</title></head><body><h1>This</h1><h2>is</h2
// ><h3>it</h3><hr><div><span>a span node</span><p>a paragraph</p><br />plain text<
// /div></body></html>