98 lines
2 KiB
Markdown
98 lines
2 KiB
Markdown
# HTML [](http://godoc.org/github.com/tdewolff/parse/html) [](http://gocover.io/github.com/tdewolff/parse/html)
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This package is an HTML5 lexer written in [Go][1]. It follows the specification at [The HTML syntax](http://www.w3.org/TR/html5/syntax.html). The lexer takes an io.Reader and converts it into tokens until the EOF.
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## Installation
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Run the following command
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go get github.com/tdewolff/parse/html
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or add the following import and run project with `go get`
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import "github.com/tdewolff/parse/html"
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## Lexer
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### Usage
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The following initializes a new Lexer with io.Reader `r`:
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``` go
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l := html.NewLexer(r)
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```
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To tokenize until EOF an error, use:
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``` go
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for {
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tt, data := l.Next()
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switch tt {
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case html.ErrorToken:
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// error or EOF set in l.Err()
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return
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case html.StartTagToken:
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// ...
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for {
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ttAttr, dataAttr := l.Next()
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if ttAttr != html.AttributeToken {
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break
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}
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// ...
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}
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// ...
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}
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}
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```
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All tokens:
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``` go
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ErrorToken TokenType = iota // extra token when errors occur
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CommentToken
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DoctypeToken
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StartTagToken
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StartTagCloseToken
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StartTagVoidToken
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EndTagToken
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AttributeToken
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TextToken
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```
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### Examples
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``` go
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package main
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import (
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"os"
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"github.com/tdewolff/parse/html"
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)
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// Tokenize HTML from stdin.
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func main() {
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l := html.NewLexer(os.Stdin)
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for {
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tt, data := l.Next()
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switch tt {
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case html.ErrorToken:
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if l.Err() != io.EOF {
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fmt.Println("Error on line", l.Line(), ":", l.Err())
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}
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return
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case html.StartTagToken:
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fmt.Println("Tag", string(data))
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for {
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ttAttr, dataAttr := l.Next()
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if ttAttr != html.AttributeToken {
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break
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}
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key := dataAttr
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val := l.AttrVal()
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fmt.Println("Attribute", string(key), "=", string(val))
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}
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// ...
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}
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}
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}
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```
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## License
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Released under the [MIT license](https://github.com/tdewolff/parse/blob/master/LICENSE.md).
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[1]: http://golang.org/ "Go Language"
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