335 lines
		
	
	
		
			7.8 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			335 lines
		
	
	
		
			7.8 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| //
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| // Blackfriday Markdown Processor
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| // Available at http://github.com/russross/blackfriday
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| //
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| // Copyright © 2011 Russ Ross <russ@russross.com>.
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| // Distributed under the Simplified BSD License.
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| // See README.md for details.
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| //
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| 
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| //
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| //
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| // LaTeX rendering backend
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| //
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| //
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| 
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| package blackfriday
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| 
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| import (
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| 	"bytes"
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| 	"strings"
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| )
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| 
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| // Latex is a type that implements the Renderer interface for LaTeX output.
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| //
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| // Do not create this directly, instead use the LatexRenderer function.
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| type Latex struct {
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| }
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| 
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| // LatexRenderer creates and configures a Latex object, which
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| // satisfies the Renderer interface.
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| //
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| // flags is a set of LATEX_* options ORed together (currently no such options
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| // are defined).
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| func LatexRenderer(flags int) Renderer {
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| 	return &Latex{}
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| }
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| 
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| func (options *Latex) GetFlags() int {
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| 	return 0
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| }
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| 
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| // render code chunks using verbatim, or listings if we have a language
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| func (options *Latex) BlockCode(out *bytes.Buffer, text []byte, info string) {
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| 	if info == "" {
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| 		out.WriteString("\n\\begin{verbatim}\n")
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| 	} else {
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| 		lang := strings.Fields(info)[0]
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| 		out.WriteString("\n\\begin{lstlisting}[language=")
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| 		out.WriteString(lang)
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| 		out.WriteString("]\n")
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| 	}
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| 	out.Write(text)
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| 	if info == "" {
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| 		out.WriteString("\n\\end{verbatim}\n")
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| 	} else {
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| 		out.WriteString("\n\\end{lstlisting}\n")
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| 	}
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| }
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| 
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| func (options *Latex) TitleBlock(out *bytes.Buffer, text []byte) {
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| 
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| }
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| 
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| func (options *Latex) BlockQuote(out *bytes.Buffer, text []byte) {
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| 	out.WriteString("\n\\begin{quotation}\n")
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| 	out.Write(text)
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| 	out.WriteString("\n\\end{quotation}\n")
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| }
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| 
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| func (options *Latex) BlockHtml(out *bytes.Buffer, text []byte) {
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| 	// a pretty lame thing to do...
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| 	out.WriteString("\n\\begin{verbatim}\n")
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| 	out.Write(text)
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| 	out.WriteString("\n\\end{verbatim}\n")
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| }
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| 
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| func (options *Latex) Header(out *bytes.Buffer, text func() bool, level int, id string) {
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| 	marker := out.Len()
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| 
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| 	switch level {
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| 	case 1:
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| 		out.WriteString("\n\\section{")
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| 	case 2:
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| 		out.WriteString("\n\\subsection{")
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| 	case 3:
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| 		out.WriteString("\n\\subsubsection{")
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| 	case 4:
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| 		out.WriteString("\n\\paragraph{")
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| 	case 5:
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| 		out.WriteString("\n\\subparagraph{")
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| 	case 6:
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| 		out.WriteString("\n\\textbf{")
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| 	}
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| 	if !text() {
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| 		out.Truncate(marker)
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| 		return
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| 	}
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| 	out.WriteString("}\n")
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| }
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| 
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| func (options *Latex) HRule(out *bytes.Buffer) {
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| 	out.WriteString("\n\\HRule\n")
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| }
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| 
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| func (options *Latex) List(out *bytes.Buffer, text func() bool, flags int) {
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| 	marker := out.Len()
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| 	if flags&LIST_TYPE_ORDERED != 0 {
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| 		out.WriteString("\n\\begin{enumerate}\n")
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| 	} else {
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| 		out.WriteString("\n\\begin{itemize}\n")
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| 	}
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| 	if !text() {
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| 		out.Truncate(marker)
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| 		return
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| 	}
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| 	if flags&LIST_TYPE_ORDERED != 0 {
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| 		out.WriteString("\n\\end{enumerate}\n")
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| 	} else {
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| 		out.WriteString("\n\\end{itemize}\n")
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| 	}
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| }
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| 
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| func (options *Latex) ListItem(out *bytes.Buffer, text []byte, flags int) {
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| 	out.WriteString("\n\\item ")
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| 	out.Write(text)
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| }
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| 
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| func (options *Latex) Paragraph(out *bytes.Buffer, text func() bool) {
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| 	marker := out.Len()
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| 	out.WriteString("\n")
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| 	if !text() {
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| 		out.Truncate(marker)
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| 		return
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| 	}
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| 	out.WriteString("\n")
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| }
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| 
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| func (options *Latex) Table(out *bytes.Buffer, header []byte, body []byte, columnData []int) {
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| 	out.WriteString("\n\\begin{tabular}{")
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| 	for _, elt := range columnData {
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| 		switch elt {
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| 		case TABLE_ALIGNMENT_LEFT:
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| 			out.WriteByte('l')
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| 		case TABLE_ALIGNMENT_RIGHT:
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| 			out.WriteByte('r')
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| 		default:
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| 			out.WriteByte('c')
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| 		}
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| 	}
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| 	out.WriteString("}\n")
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| 	out.Write(header)
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| 	out.WriteString(" \\\\\n\\hline\n")
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| 	out.Write(body)
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| 	out.WriteString("\n\\end{tabular}\n")
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| }
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| 
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| func (options *Latex) TableRow(out *bytes.Buffer, text []byte) {
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| 	if out.Len() > 0 {
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| 		out.WriteString(" \\\\\n")
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| 	}
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| 	out.Write(text)
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| }
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| 
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| func (options *Latex) TableHeaderCell(out *bytes.Buffer, text []byte, align int) {
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| 	if out.Len() > 0 {
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| 		out.WriteString(" & ")
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| 	}
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| 	out.Write(text)
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| }
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| 
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| func (options *Latex) TableCell(out *bytes.Buffer, text []byte, align int) {
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| 	if out.Len() > 0 {
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| 		out.WriteString(" & ")
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| 	}
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| 	out.Write(text)
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| }
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| 
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| // TODO: this
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| func (options *Latex) Footnotes(out *bytes.Buffer, text func() bool) {
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| 
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| }
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| 
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| func (options *Latex) FootnoteItem(out *bytes.Buffer, name, text []byte, flags int) {
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| 
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| }
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| 
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| func (options *Latex) AutoLink(out *bytes.Buffer, link []byte, kind int) {
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| 	out.WriteString("\\href{")
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| 	if kind == LINK_TYPE_EMAIL {
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| 		out.WriteString("mailto:")
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| 	}
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| 	out.Write(link)
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| 	out.WriteString("}{")
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| 	out.Write(link)
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| 	out.WriteString("}")
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| }
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| 
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| func (options *Latex) CodeSpan(out *bytes.Buffer, text []byte) {
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| 	out.WriteString("\\texttt{")
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| 	escapeSpecialChars(out, text)
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| 	out.WriteString("}")
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| }
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| 
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| func (options *Latex) DoubleEmphasis(out *bytes.Buffer, text []byte) {
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| 	out.WriteString("\\textbf{")
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| 	out.Write(text)
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| 	out.WriteString("}")
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| }
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| 
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| func (options *Latex) Emphasis(out *bytes.Buffer, text []byte) {
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| 	out.WriteString("\\textit{")
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| 	out.Write(text)
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| 	out.WriteString("}")
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| }
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| 
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| func (options *Latex) Image(out *bytes.Buffer, link []byte, title []byte, alt []byte) {
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| 	if bytes.HasPrefix(link, []byte("http://")) || bytes.HasPrefix(link, []byte("https://")) {
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| 		// treat it like a link
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| 		out.WriteString("\\href{")
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| 		out.Write(link)
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| 		out.WriteString("}{")
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| 		out.Write(alt)
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| 		out.WriteString("}")
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| 	} else {
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| 		out.WriteString("\\includegraphics{")
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| 		out.Write(link)
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| 		out.WriteString("}")
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| 	}
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| }
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| 
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| func (options *Latex) LineBreak(out *bytes.Buffer) {
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| 	out.WriteString(" \\\\\n")
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| }
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| 
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| func (options *Latex) Link(out *bytes.Buffer, link []byte, title []byte, content []byte) {
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| 	out.WriteString("\\href{")
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| 	out.Write(link)
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| 	out.WriteString("}{")
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| 	out.Write(content)
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| 	out.WriteString("}")
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| }
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| 
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| func (options *Latex) RawHtmlTag(out *bytes.Buffer, tag []byte) {
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| }
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| 
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| func (options *Latex) TripleEmphasis(out *bytes.Buffer, text []byte) {
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| 	out.WriteString("\\textbf{\\textit{")
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| 	out.Write(text)
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| 	out.WriteString("}}")
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| }
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| 
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| func (options *Latex) StrikeThrough(out *bytes.Buffer, text []byte) {
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| 	out.WriteString("\\sout{")
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| 	out.Write(text)
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| 	out.WriteString("}")
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| }
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| 
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| // TODO: this
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| func (options *Latex) FootnoteRef(out *bytes.Buffer, ref []byte, id int) {
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| 
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| }
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| 
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| func needsBackslash(c byte) bool {
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| 	for _, r := range []byte("_{}%$&\\~#") {
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| 		if c == r {
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| 			return true
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| 		}
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| 	}
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| 	return false
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| }
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| 
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| func escapeSpecialChars(out *bytes.Buffer, text []byte) {
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| 	for i := 0; i < len(text); i++ {
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| 		// directly copy normal characters
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| 		org := i
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| 
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| 		for i < len(text) && !needsBackslash(text[i]) {
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| 			i++
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| 		}
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| 		if i > org {
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| 			out.Write(text[org:i])
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| 		}
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| 
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| 		// escape a character
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| 		if i >= len(text) {
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| 			break
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| 		}
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| 		out.WriteByte('\\')
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| 		out.WriteByte(text[i])
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| 	}
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| }
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| 
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| func (options *Latex) Entity(out *bytes.Buffer, entity []byte) {
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| 	// TODO: convert this into a unicode character or something
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| 	out.Write(entity)
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| }
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| 
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| func (options *Latex) NormalText(out *bytes.Buffer, text []byte) {
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| 	escapeSpecialChars(out, text)
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| }
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| 
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| // header and footer
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| func (options *Latex) DocumentHeader(out *bytes.Buffer) {
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| 	out.WriteString("\\documentclass{article}\n")
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| 	out.WriteString("\n")
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| 	out.WriteString("\\usepackage{graphicx}\n")
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| 	out.WriteString("\\usepackage{listings}\n")
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| 	out.WriteString("\\usepackage[margin=1in]{geometry}\n")
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| 	out.WriteString("\\usepackage[utf8]{inputenc}\n")
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| 	out.WriteString("\\usepackage{verbatim}\n")
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| 	out.WriteString("\\usepackage[normalem]{ulem}\n")
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| 	out.WriteString("\\usepackage{hyperref}\n")
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| 	out.WriteString("\n")
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| 	out.WriteString("\\hypersetup{colorlinks,%\n")
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| 	out.WriteString("  citecolor=black,%\n")
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| 	out.WriteString("  filecolor=black,%\n")
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| 	out.WriteString("  linkcolor=black,%\n")
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| 	out.WriteString("  urlcolor=black,%\n")
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| 	out.WriteString("  pdfstartview=FitH,%\n")
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| 	out.WriteString("  breaklinks=true,%\n")
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| 	out.WriteString("  pdfauthor={Blackfriday Markdown Processor v")
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| 	out.WriteString(VERSION)
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| 	out.WriteString("}}\n")
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| 	out.WriteString("\n")
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| 	out.WriteString("\\newcommand{\\HRule}{\\rule{\\linewidth}{0.5mm}}\n")
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| 	out.WriteString("\\addtolength{\\parskip}{0.5\\baselineskip}\n")
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| 	out.WriteString("\\parindent=0pt\n")
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| 	out.WriteString("\n")
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| 	out.WriteString("\\begin{document}\n")
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| }
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| 
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| func (options *Latex) DocumentFooter(out *bytes.Buffer) {
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| 	out.WriteString("\n\\end{document}\n")
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| }
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