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// |
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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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// LaTeX rendering backend |
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// |
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// |
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package blackfriday |
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import ( |
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"bytes" |
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"strings" |
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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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// 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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func (options *Latex) GetFlags() int { |
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return 0 |
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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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func (options *Latex) TitleBlock(out *bytes.Buffer, text []byte) { |
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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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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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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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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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func (options *Latex) HRule(out *bytes.Buffer) { |
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out.WriteString("\n\\HRule\n") |
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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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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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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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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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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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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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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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// TODO: this |
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func (options *Latex) Footnotes(out *bytes.Buffer, text func() bool) { |
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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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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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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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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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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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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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func (options *Latex) LineBreak(out *bytes.Buffer) { |
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out.WriteString(" \\\\\n") |
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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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func (options *Latex) RawHtmlTag(out *bytes.Buffer, tag []byte) { |
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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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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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// 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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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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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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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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// 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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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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func (options *Latex) NormalText(out *bytes.Buffer, text []byte) { |
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escapeSpecialChars(out, text) |
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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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func (options *Latex) DocumentFooter(out *bytes.Buffer) { |
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out.WriteString("\n\\end{document}\n") |
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} |