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@rtfb
Created July 9, 2017 12:35
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This example overrides the default HTML renderer to produce only header and footer, but omit the document body. That's an equivalent of using `HTML_OMIT_CONTENTS` with Blackfriday v1.
package main
import (
"fmt"
"io"
"github.com/russross/blackfriday.v2"
)
// OmitContentsRenderer is a thing.
type OmitContentsRenderer struct {
defaultR *blackfriday.HTMLRenderer
doneWithHeader bool
}
// RenderHeader writes HTML document preamble and TOC if requested.
func (r *OmitContentsRenderer) RenderHeader(w io.Writer, ast *blackfriday.Node) {
r.defaultR.RenderHeader(w, ast)
r.doneWithHeader = true
}
// RenderFooter writes HTML document footer.
func (r *OmitContentsRenderer) RenderFooter(w io.Writer, ast *blackfriday.Node) {
r.defaultR.RenderFooter(w, ast)
}
// RenderNode is RenderNode.
func (r *OmitContentsRenderer) RenderNode(w io.Writer, node *blackfriday.Node, entering bool) blackfriday.WalkStatus {
if r.doneWithHeader {
return blackfriday.Terminate
}
return r.defaultR.RenderNode(w, node, entering)
}
func main() {
md := "# Heading1\n\nIntroduction.\n\n## Heading2\n\nConclusions."
defaultR := blackfriday.NewHTMLRenderer(blackfriday.HTMLRendererParameters{
Flags: blackfriday.TOC,
})
or := OmitContentsRenderer{defaultR: defaultR}
html := blackfriday.Run([]byte(md), blackfriday.WithRenderer(&or))
fmt.Println(string(html))
}
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