start of revision control

lib/latex-loader.js

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+var op = "\\[";
+var ed = "\\]";
+
+/**
+ * Is there going to be anything to convert here?
+ */
+function hasLaTeX(input) {
+  return input.indexOf(op) + input.indexOf(ed) >= 0;
+}
+
+/**
+ * We look for MathJax/KaTeX style data, and make sure
+ * it is escaped properly so that JSX conversion will
+ * still work.
+ */
+function escapeBlockLaTeX(source) {
+  // we can't do this with regexp, unfortunately.
+  var from = 0, curr, term;
+  var newsource = "", latex;
+  for(curr = source.indexOf(op, from); curr !== -1; from = term + ed.length, curr = source.indexOf(op, from)) {
+    newsource += source.substring(from, curr);
+    term = source.indexOf(ed, from);
+    if(term === -1) {
+      // that's a problem...
+      throw new Error("improperly closed LaTeX encountered!");
+    }
+    latex = source.substring(curr, term + ed.length);
+    latex = latex.replace(/([{}])/g,"{'$1'}");
+    newsource += latex;
+  }
+  return newsource + source.substring(from);
+}
+
+/**
+ * ...
+ */
+function colorPreProcess(input) {
+  var regexp = new RegExp("([A-Z]+)\\[([^\\]]+)\\]",'g');
+  var output = input.replace(regexp, function(_,color,content) {
+    if(content.indexOf(" ")!==-1) { content = " " + content; }
+    return "{\\color{"+color.toLowerCase()+"}"+content.replace(/ /g,"\\ ")+"}";
+  });
+  return output;
+};
+
+module.exports = function(source) {
+  this.cacheable();
+  if (!hasLaTeX(source)) return source;
+  return escapeBlockLaTeX(colorPreProcess(source));
+};
+
+