| # -*- coding: utf-8 -*- |
| # |
| #-- |
| # Copyright (C) 2009-2016 Thomas Leitner <t_leitner@gmx.at> |
| # |
| # This file is part of kramdown which is licensed under the MIT. |
| #++ |
| # |
| |
| require 'set' |
| require 'kramdown/converter' |
| |
| module Kramdown |
| |
| module Converter |
| |
| # Converts an element tree to LaTeX. |
| # |
| # This converter uses ideas from other Markdown-to-LaTeX converters like Pandoc and Maruku. |
| # |
| # You can customize this converter by sub-classing it and overriding the +convert_NAME+ methods. |
| # Each such method takes the following parameters: |
| # |
| # [+el+] The element of type +NAME+ to be converted. |
| # |
| # [+opts+] A hash containing processing options that are passed down from parent elements. The |
| # key :parent is always set and contains the parent element as value. |
| # |
| # The return value of such a method has to be a string containing the element +el+ formatted |
| # correctly as LaTeX markup. |
| class Latex < Base |
| |
| # Initialize the LaTeX converter with the +root+ element and the conversion +options+. |
| def initialize(root, options) |
| super |
| @data[:packages] = Set.new |
| end |
| |
| # Dispatch the conversion of the element +el+ to a +convert_TYPE+ method using the +type+ of |
| # the element. |
| def convert(el, opts = {}) |
| send("convert_#{el.type}", el, opts) |
| end |
| |
| # Return the converted content of the children of +el+ as a string. |
| def inner(el, opts) |
| result = '' |
| options = opts.dup.merge(:parent => el) |
| el.children.each_with_index do |inner_el, index| |
| options[:index] = index |
| options[:result] = result |
| result << send("convert_#{inner_el.type}", inner_el, options) |
| end |
| result |
| end |
| |
| def convert_root(el, opts) |
| inner(el, opts) |
| end |
| |
| def convert_blank(el, opts) |
| opts[:result] =~ /\n\n\Z|\A\Z/ ? "" : "\n" |
| end |
| |
| def convert_text(el, opts) |
| escape(el.value) |
| end |
| |
| def convert_p(el, opts) |
| if el.children.size == 1 && el.children.first.type == :img && !(img = convert_img(el.children.first, opts)).empty? |
| convert_standalone_image(el, opts, img) |
| else |
| "#{latex_link_target(el)}#{inner(el, opts)}\n\n" |
| end |
| end |
| |
| # Helper method used by +convert_p+ to convert a paragraph that only contains a single :img |
| # element. |
| def convert_standalone_image(el, opts, img) |
| attrs = attribute_list(el) |
| "\\begin{figure}#{attrs}\n\\begin{center}\n#{img}\n\\end{center}\n\\caption{#{escape(el.children.first.attr['alt'])}}\n#{latex_link_target(el, true)}\n\\end{figure}#{attrs}\n" |
| end |
| |
| def convert_codeblock(el, opts) |
| show_whitespace = el.attr['class'].to_s =~ /\bshow-whitespaces\b/ |
| lang = extract_code_language(el.attr) |
| |
| if @options[:syntax_highlighter] == :minted && |
| (highlighted_code = highlight_code(el.value, lang, :block)) |
| @data[:packages] << 'minted' |
| "#{latex_link_target(el)}#{highlighted_code}\n" |
| elsif show_whitespace || lang |
| options = [] |
| options << "showspaces=%s,showtabs=%s" % (show_whitespace ? ['true', 'true'] : ['false', 'false']) |
| options << "language=#{lang}" if lang |
| options << "basicstyle=\\ttfamily\\footnotesize,columns=fixed,frame=tlbr" |
| id = el.attr['id'] |
| options << "label=#{id}" if id |
| attrs = attribute_list(el) |
| "#{latex_link_target(el)}\\begin{lstlisting}[#{options.join(',')}]\n#{el.value}\n\\end{lstlisting}#{attrs}\n" |
| else |
| "#{latex_link_target(el)}\\begin{verbatim}#{el.value}\\end{verbatim}\n" |
| end |
| end |
| |
| def convert_blockquote(el, opts) |
| latex_environment(el.children.size > 1 ? 'quotation' : 'quote', el, inner(el, opts)) |
| end |
| |
| def convert_header(el, opts) |
| type = @options[:latex_headers][output_header_level(el.options[:level]) - 1] |
| if ((id = el.attr['id']) || |
| (@options[:auto_ids] && (id = generate_id(el.options[:raw_text])))) && in_toc?(el) |
| "\\#{type}{#{inner(el, opts)}}\\hypertarget{#{id}}{}\\label{#{id}}\n\n" |
| else |
| "\\#{type}*{#{inner(el, opts)}}\n\n" |
| end |
| end |
| |
| def convert_hr(el, opts) |
| attrs = attribute_list(el) |
| "#{latex_link_target(el)}\\begin{center}#{attrs}\n\\rule{3in}{0.4pt}\n\\end{center}#{attrs}\n" |
| end |
| |
| def convert_ul(el, opts) |
| if !@data[:has_toc] && (el.options[:ial][:refs].include?('toc') rescue nil) |
| @data[:has_toc] = true |
| '\tableofcontents' |
| else |
| latex_environment(el.type == :ul ? 'itemize' : 'enumerate', el, inner(el, opts)) |
| end |
| end |
| alias :convert_ol :convert_ul |
| |
| def convert_dl(el, opts) |
| latex_environment('description', el, inner(el, opts)) |
| end |
| |
| def convert_li(el, opts) |
| "\\item #{latex_link_target(el, true)}#{inner(el, opts).sub(/\n+\Z/, '')}\n" |
| end |
| |
| def convert_dt(el, opts) |
| "\\item[#{inner(el, opts)}] " |
| end |
| |
| def convert_dd(el, opts) |
| "#{latex_link_target(el)}#{inner(el, opts)}\n\n" |
| end |
| |
| def convert_html_element(el, opts) |
| if el.value == 'i' || el.value == 'em' |
| "\\emph{#{inner(el, opts)}}" |
| elsif el.value == 'b' || el.value == 'strong' |
| "\\textbf{#{inner(el, opts)}}" |
| else |
| warning("Can't convert HTML element") |
| '' |
| end |
| end |
| |
| def convert_xml_comment(el, opts) |
| el.value.split(/\n/).map {|l| "% #{l}"}.join("\n") + "\n" |
| end |
| |
| def convert_xml_pi(el, opts) |
| warning("Can't convert XML PI") |
| '' |
| end |
| |
| TABLE_ALIGNMENT_CHAR = {:default => 'l', :left => 'l', :center => 'c', :right => 'r'} # :nodoc: |
| |
| def convert_table(el, opts) |
| @data[:packages] << 'longtable' |
| align = el.options[:alignment].map {|a| TABLE_ALIGNMENT_CHAR[a]}.join('|') |
| attrs = attribute_list(el) |
| "#{latex_link_target(el)}\\begin{longtable}{|#{align}|}#{attrs}\n\\hline\n#{inner(el, opts)}\\hline\n\\end{longtable}#{attrs}\n\n" |
| end |
| |
| def convert_thead(el, opts) |
| "#{inner(el, opts)}\\hline\n" |
| end |
| |
| def convert_tbody(el, opts) |
| inner(el, opts) |
| end |
| |
| def convert_tfoot(el, opts) |
| "\\hline \\hline \n#{inner(el, opts)}" |
| end |
| |
| def convert_tr(el, opts) |
| el.children.map {|c| send("convert_#{c.type}", c, opts)}.join(' & ') << "\\\\\n" |
| end |
| |
| def convert_td(el, opts) |
| inner(el, opts) |
| end |
| |
| def convert_comment(el, opts) |
| el.value.split(/\n/).map {|l| "% #{l}"}.join("\n") << "\n" |
| end |
| |
| def convert_br(el, opts) |
| res = "\\newline" |
| res << "\n" if (c = opts[:parent].children[opts[:index]+1]) && (c.type != :text || c.value !~ /^\s*\n/) |
| res |
| end |
| |
| def convert_a(el, opts) |
| url = el.attr['href'] |
| if url.start_with?('#') |
| "\\hyperlink{#{escape(url[1..-1])}}{#{inner(el, opts)}}" |
| else |
| "\\href{#{escape(url)}}{#{inner(el, opts)}}" |
| end |
| end |
| |
| def convert_img(el, opts) |
| line = el.options[:location] |
| if el.attr['src'] =~ /^(https?|ftps?):\/\// |
| warning("Cannot include non-local image#{line ? " (line #{line})" : ''}") |
| '' |
| elsif !el.attr['src'].empty? |
| @data[:packages] << 'graphicx' |
| "#{latex_link_target(el)}\\includegraphics{#{el.attr['src']}}" |
| else |
| warning("Cannot include image with empty path#{line ? " (line #{line})" : ''}") |
| '' |
| end |
| end |
| |
| def convert_codespan(el, opts) |
| lang = extract_code_language(el.attr) |
| if @options[:syntax_highlighter] == :minted && |
| (highlighted_code = highlight_code(el.value, lang, :span)) |
| @data[:packages] << 'minted' |
| "#{latex_link_target(el)}#{highlighted_code}" |
| else |
| "\\texttt{#{latex_link_target(el)}#{escape(el.value)}}" |
| end |
| end |
| |
| def convert_footnote(el, opts) |
| @data[:packages] << 'fancyvrb' |
| "\\footnote{#{inner(el.value, opts).rstrip}}" |
| end |
| |
| def convert_raw(el, opts) |
| if !el.options[:type] || el.options[:type].empty? || el.options[:type].include?('latex') |
| el.value + (el.options[:category] == :block ? "\n" : '') |
| else |
| '' |
| end |
| end |
| |
| def convert_em(el, opts) |
| "\\emph{#{latex_link_target(el)}#{inner(el, opts)}}" |
| end |
| |
| def convert_strong(el, opts) |
| "\\textbf{#{latex_link_target(el)}#{inner(el, opts)}}" |
| end |
| |
| # Inspired by Maruku: entity conversion table based on the one from htmltolatex |
| # (http://sourceforge.net/projects/htmltolatex/), with some small adjustments/additions |
| ENTITY_CONV_TABLE = { |
| 913 => ['$A$'], |
| 914 => ['$B$'], |
| 915 => ['$\Gamma$'], |
| 916 => ['$\Delta$'], |
| 917 => ['$E$'], |
| 918 => ['$Z$'], |
| 919 => ['$H$'], |
| 920 => ['$\Theta$'], |
| 921 => ['$I$'], |
| 922 => ['$K$'], |
| 923 => ['$\Lambda$'], |
| 924 => ['$M$'], |
| 925 => ['$N$'], |
| 926 => ['$\Xi$'], |
| 927 => ['$O$'], |
| 928 => ['$\Pi$'], |
| 929 => ['$P$'], |
| 931 => ['$\Sigma$'], |
| 932 => ['$T$'], |
| 933 => ['$Y$'], |
| 934 => ['$\Phi$'], |
| 935 => ['$X$'], |
| 936 => ['$\Psi$'], |
| 937 => ['$\Omega$'], |
| 945 => ['$\alpha$'], |
| 946 => ['$\beta$'], |
| 947 => ['$\gamma$'], |
| 948 => ['$\delta$'], |
| 949 => ['$\epsilon$'], |
| 950 => ['$\zeta$'], |
| 951 => ['$\eta$'], |
| 952 => ['$\theta$'], |
| 953 => ['$\iota$'], |
| 954 => ['$\kappa$'], |
| 955 => ['$\lambda$'], |
| 956 => ['$\mu$'], |
| 957 => ['$\nu$'], |
| 958 => ['$\xi$'], |
| 959 => ['$o$'], |
| 960 => ['$\pi$'], |
| 961 => ['$\rho$'], |
| 963 => ['$\sigma$'], |
| 964 => ['$\tau$'], |
| 965 => ['$\upsilon$'], |
| 966 => ['$\phi$'], |
| 967 => ['$\chi$'], |
| 968 => ['$\psi$'], |
| 969 => ['$\omega$'], |
| 962 => ['$\varsigma$'], |
| 977 => ['$\vartheta$'], |
| 982 => ['$\varpi$'], |
| 8230 => ['\ldots'], |
| 8242 => ['$\prime$'], |
| 8254 => ['-'], |
| 8260 => ['/'], |
| 8472 => ['$\wp$'], |
| 8465 => ['$\Im$'], |
| 8476 => ['$\Re$'], |
| 8501 => ['$\aleph$'], |
| 8226 => ['$\bullet$'], |
| 8482 => ['$^{\rm TM}$'], |
| 8592 => ['$\leftarrow$'], |
| 8594 => ['$\rightarrow$'], |
| 8593 => ['$\uparrow$'], |
| 8595 => ['$\downarrow$'], |
| 8596 => ['$\leftrightarrow$'], |
| 8629 => ['$\hookleftarrow$'], |
| 8657 => ['$\Uparrow$'], |
| 8659 => ['$\Downarrow$'], |
| 8656 => ['$\Leftarrow$'], |
| 8658 => ['$\Rightarrow$'], |
| 8660 => ['$\Leftrightarrow$'], |
| 8704 => ['$\forall$'], |
| 8706 => ['$\partial$'], |
| 8707 => ['$\exists$'], |
| 8709 => ['$\emptyset$'], |
| 8711 => ['$\nabla$'], |
| 8712 => ['$\in$'], |
| 8715 => ['$\ni$'], |
| 8713 => ['$\notin$'], |
| 8721 => ['$\sum$'], |
| 8719 => ['$\prod$'], |
| 8722 => ['$-$'], |
| 8727 => ['$\ast$'], |
| 8730 => ['$\surd$'], |
| 8733 => ['$\propto$'], |
| 8734 => ['$\infty$'], |
| 8736 => ['$\angle$'], |
| 8743 => ['$\wedge$'], |
| 8744 => ['$\vee$'], |
| 8745 => ['$\cup$'], |
| 8746 => ['$\cap$'], |
| 8747 => ['$\int$'], |
| 8756 => ['$\therefore$', 'amssymb'], |
| 8764 => ['$\sim$'], |
| 8776 => ['$\approx$'], |
| 8773 => ['$\cong$'], |
| 8800 => ['$\neq$'], |
| 8801 => ['$\equiv$'], |
| 8804 => ['$\leq$'], |
| 8805 => ['$\geq$'], |
| 8834 => ['$\subset$'], |
| 8835 => ['$\supset$'], |
| 8838 => ['$\subseteq$'], |
| 8839 => ['$\supseteq$'], |
| 8836 => ['$\nsubset$', 'amssymb'], |
| 8853 => ['$\oplus$'], |
| 8855 => ['$\otimes$'], |
| 8869 => ['$\perp$'], |
| 8901 => ['$\cdot$'], |
| 8968 => ['$\rceil$'], |
| 8969 => ['$\lceil$'], |
| 8970 => ['$\lfloor$'], |
| 8971 => ['$\rfloor$'], |
| 9001 => ['$\rangle$'], |
| 9002 => ['$\langle$'], |
| 9674 => ['$\lozenge$', 'amssymb'], |
| 9824 => ['$\spadesuit$'], |
| 9827 => ['$\clubsuit$'], |
| 9829 => ['$\heartsuit$'], |
| 9830 => ['$\diamondsuit$'], |
| 38 => ['\&'], |
| 34 => ['"'], |
| 39 => ['\''], |
| 169 => ['\copyright'], |
| 60 => ['\textless'], |
| 62 => ['\textgreater'], |
| 338 => ['\OE'], |
| 339 => ['\oe'], |
| 352 => ['\v{S}'], |
| 353 => ['\v{s}'], |
| 376 => ['\"Y'], |
| 710 => ['\textasciicircum'], |
| 732 => ['\textasciitilde'], |
| 8211 => ['--'], |
| 8212 => ['---'], |
| 8216 => ['`'], |
| 8217 => ['\''], |
| 8220 => ['``'], |
| 8221 => ['\'\''], |
| 8224 => ['\dag'], |
| 8225 => ['\ddag'], |
| 8240 => ['\permil', 'wasysym'], |
| 8364 => ['\euro', 'eurosym'], |
| 8249 => ['\guilsinglleft'], |
| 8250 => ['\guilsinglright'], |
| 8218 => ['\quotesinglbase', 'mathcomp'], |
| 8222 => ['\quotedblbase', 'mathcomp'], |
| 402 => ['\textflorin', 'mathcomp'], |
| 381 => ['\v{Z}'], |
| 382 => ['\v{z}'], |
| 160 => ['~'], |
| 161 => ['\textexclamdown'], |
| 163 => ['\pounds'], |
| 164 => ['\currency', 'wasysym'], |
| 165 => ['\textyen', 'textcomp'], |
| 166 => ['\brokenvert', 'wasysym'], |
| 167 => ['\S'], |
| 171 => ['\guillemotleft'], |
| 187 => ['\guillemotright'], |
| 174 => ['\textregistered'], |
| 170 => ['\textordfeminine'], |
| 172 => ['$\neg$'], |
| 173 => ['\-'], |
| 176 => ['$\degree$', 'mathabx'], |
| 177 => ['$\pm$'], |
| 180 => ['\''], |
| 181 => ['$\mu$'], |
| 182 => ['\P'], |
| 183 => ['$\cdot$'], |
| 186 => ['\textordmasculine'], |
| 162 => ['\cent', 'wasysym'], |
| 185 => ['$^1$'], |
| 178 => ['$^2$'], |
| 179 => ['$^3$'], |
| 189 => ['$\frac{1}{2}$'], |
| 188 => ['$\frac{1}{4}$'], |
| 190 => ['$\frac{3}{4}'], |
| 192 => ['\`A'], |
| 193 => ['\\\'A'], |
| 194 => ['\^A'], |
| 195 => ['\~A'], |
| 196 => ['\"A'], |
| 197 => ['\AA'], |
| 198 => ['\AE'], |
| 199 => ['\cC'], |
| 200 => ['\`E'], |
| 201 => ['\\\'E'], |
| 202 => ['\^E'], |
| 203 => ['\"E'], |
| 204 => ['\`I'], |
| 205 => ['\\\'I'], |
| 206 => ['\^I'], |
| 207 => ['\"I'], |
| 208 => ['$\eth$', 'amssymb'], |
| 209 => ['\~N'], |
| 210 => ['\`O'], |
| 211 => ['\\\'O'], |
| 212 => ['\^O'], |
| 213 => ['\~O'], |
| 214 => ['\"O'], |
| 215 => ['$\times$'], |
| 216 => ['\O'], |
| 217 => ['\`U'], |
| 218 => ['\\\'U'], |
| 219 => ['\^U'], |
| 220 => ['\"U'], |
| 221 => ['\\\'Y'], |
| 222 => ['\Thorn', 'wasysym'], |
| 223 => ['\ss'], |
| 224 => ['\`a'], |
| 225 => ['\\\'a'], |
| 226 => ['\^a'], |
| 227 => ['\~a'], |
| 228 => ['\"a'], |
| 229 => ['\aa'], |
| 230 => ['\ae'], |
| 231 => ['\cc'], |
| 232 => ['\`e'], |
| 233 => ['\\\'e'], |
| 234 => ['\^e'], |
| 235 => ['\"e'], |
| 236 => ['\`i'], |
| 237 => ['\\\'i'], |
| 238 => ['\^i'], |
| 239 => ['\"i'], |
| 240 => ['$\eth$'], |
| 241 => ['\~n'], |
| 242 => ['\`o'], |
| 243 => ['\\\'o'], |
| 244 => ['\^o'], |
| 245 => ['\~o'], |
| 246 => ['\"o'], |
| 247 => ['$\divide$'], |
| 248 => ['\o'], |
| 249 => ['\`u'], |
| 250 => ['\\\'u'], |
| 251 => ['\^u'], |
| 252 => ['\"u'], |
| 253 => ['\\\'y'], |
| 254 => ['\thorn', 'wasysym'], |
| 255 => ['\"y'], |
| 8201 => ['\thinspace'], |
| 8194 => ['\hskip .5em\relax'], |
| 8195 => ['\quad'], |
| } # :nodoc: |
| ENTITY_CONV_TABLE.each {|k,v| ENTITY_CONV_TABLE[k][0].insert(-1, '{}')} |
| |
| def entity_to_latex(entity) |
| text, package = ENTITY_CONV_TABLE[entity.code_point] |
| if text |
| @data[:packages] << package if package |
| text |
| else |
| warning("Couldn't find entity with code #{entity.code_point} in substitution table!") |
| '' |
| end |
| end |
| |
| def convert_entity(el, opts) |
| entity_to_latex(el.value) |
| end |
| |
| TYPOGRAPHIC_SYMS = { |
| :mdash => '---', :ndash => '--', :hellip => '\ldots{}', |
| :laquo_space => '\guillemotleft{}~', :raquo_space => '~\guillemotright{}', |
| :laquo => '\guillemotleft{}', :raquo => '\guillemotright{}' |
| } # :nodoc: |
| def convert_typographic_sym(el, opts) |
| TYPOGRAPHIC_SYMS[el.value] |
| end |
| |
| def convert_smart_quote(el, opts) |
| res = entity_to_latex(smart_quote_entity(el)).chomp('{}') |
| res << "{}" if ((nel = opts[:parent].children[opts[:index]+1]) && nel.type == :smart_quote) || res =~ /\w$/ |
| res |
| end |
| |
| def convert_math(el, opts) |
| @data[:packages] += %w[amssymb amsmath amsthm amsfonts] |
| if el.options[:category] == :block |
| if el.value =~ /\A\s*\\begin\{/ |
| el.value |
| else |
| latex_environment('displaymath', el, el.value) |
| end |
| else |
| "$#{el.value}$" |
| end |
| end |
| |
| def convert_abbreviation(el, opts) |
| @data[:packages] += %w[acronym] |
| "\\ac{#{normalize_abbreviation_key(el.value)}}" |
| end |
| |
| # Normalize the abbreviation key so that it only contains allowed ASCII character |
| def normalize_abbreviation_key(key) |
| key.gsub(/\W/) {|m| m.unpack('H*').first} |
| end |
| |
| # Wrap the +text+ inside a LaTeX environment of type +type+. The element +el+ is passed on to |
| # the method #attribute_list -- the resulting string is appended to both the \\begin and the |
| # \\end lines of the LaTeX environment for easier post-processing of LaTeX environments. |
| def latex_environment(type, el, text) |
| attrs = attribute_list(el) |
| "\\begin{#{type}}#{latex_link_target(el)}#{attrs}\n#{text.rstrip}\n\\end{#{type}}#{attrs}\n" |
| end |
| |
| # Return a string containing a valid \hypertarget command if the element has an ID defined, or |
| # +nil+ otherwise. If the parameter +add_label+ is +true+, a \label command will also be used |
| # additionally to the \hypertarget command. |
| def latex_link_target(el, add_label = false) |
| if (id = el.attr['id']) |
| "\\hypertarget{#{id}}{}" << (add_label ? "\\label{#{id}}" : '') |
| else |
| nil |
| end |
| end |
| |
| # Return a LaTeX comment containing all attributes as 'key="value"' pairs. |
| def attribute_list(el) |
| attrs = el.attr.map {|k,v| v.nil? ? '' : " #{k}=\"#{v.to_s}\""}.compact.sort.join('') |
| attrs = " % #{attrs}" if !attrs.empty? |
| attrs |
| end |
| |
| ESCAPE_MAP = { |
| "^" => "\\^{}", |
| "\\" => "\\textbackslash{}", |
| "~" => "\\ensuremath{\\sim}", |
| "|" => "\\textbar{}", |
| "<" => "\\textless{}", |
| ">" => "\\textgreater{}" |
| }.merge(Hash[*("{}$%&_#".scan(/./).map {|c| [c, "\\#{c}"]}.flatten)]) # :nodoc: |
| ESCAPE_RE = Regexp.union(*ESCAPE_MAP.collect {|k,v| k}) # :nodoc: |
| |
| # Escape the special LaTeX characters in the string +str+. |
| def escape(str) |
| str.gsub(ESCAPE_RE) {|m| ESCAPE_MAP[m]} |
| end |
| |
| end |
| |
| end |
| end |
