code: function getShash() {
    const type = NodeType.ShashType;
    const token = tokens[pos];
    const line = token.ln;
    const column = token.col;
    const end = token.shashEnd;
    let content = [];
  
    // Skip `#`.
    pos++;
  
    while (pos < end) {
      if (checkIdentOrInterpolation(pos)) {
        content = content.concat(getIdentOrInterpolation());
      } else if (checkPartialIdent(pos)) {
        content.push(getIdent());
      } else break;
    }
  
    return newNode(type, content, line, column);
  }
docs: Get node with a hexadecimal number (e.g. `#fff`) inside a simple selector
  @return {Node}