Function buildHTML

static/katex/katex.mjs:6504–6584

* Take an entire parse tree, and build it into an appropriate set of HTML * nodes.

(tree, options)

function buildHTML(tree, options) {
  // Strip off outer tag wrapper for processing below.
  let tag = null;

  if (tree.length === 1 && tree[0].type === "tag") {
    tag = tree[0].tag;
    tree = tree[0].body;
  } // Build the expression contained in the tree


  const expression = buildExpression(tree, options, true);
  const children = []; // Create one base node for each chunk between potential line breaks.
  // The TeXBook [p.173] says "A formula will be broken only after a
  // relation symbol like $=$ or $<$ or $\rightarrow$, or after a binary
  // operation symbol like $+$ or $-$ or $\times$, where the relation or
  // binary operation is on the ``outer level'' of the formula (i.e., not
  // enclosed in {...} and not part of an \over construction)."

  let parts = [];

  for (let i = 0; i < expression.length; i++) {
    parts.push(expression[i]);

    if (expression[i].hasClass("mbin") || expression[i].hasClass("mrel") || expression[i].hasClass("allowbreak")) {
      // Put any post-operator glue on same line as operator.
      // Watch for \nobreak along the way, and stop at \newline.
      let nobreak = false;

      while (i < expression.length - 1 && expression[i + 1].hasClass("mspace") && !expression[i + 1].hasClass("newline")) {
        i++;
        parts.push(expression[i]);

        if (expression[i].hasClass("nobreak")) {
          nobreak = true;
        }
      } // Don't allow break if \nobreak among the post-operator glue.


      if (!nobreak) {
        children.push(buildHTMLUnbreakable(parts, options));
        parts = [];
      }
    } else if (expression[i].hasClass("newline")) {
      // Write the line except the newline
      parts.pop();

      if (parts.length > 0) {
        children.push(buildHTMLUnbreakable(parts, options));
        parts = [];
      } // Put the newline at the top level


      children.push(expression[i]);
    }
  }

  if (parts.length > 0) {
    children.push(buildHTMLUnbreakable(parts, options));