code: function isRemovedToken(context, token) {
    var removedNodes = context.removedNodes;
    var nodeIdx = removedNodes.length - 1;
  
    // Find the last removed node which could possibly contain this token.
    while (nodeIdx >= 0 && startOf(removedNodes[nodeIdx]) > startOf(token)) {
      nodeIdx--;
    }
  
    var node = removedNodes[nodeIdx];
  
    // This token couldn't be removed if not contained within the removed node.
    if (nodeIdx === -1 || endOf(node) < endOf(token)) {
      return false;
    }
  
    // Iterate through the tokens contained by the removed node to find a match.
    var tokens = context.ast.tokens;
    var tokenIdx = findTokenIndex(tokens, startOf(node));
    while (endOf(tokens[tokenIdx]) <= endOf(node)) {
      if (token === tokens[tokenIdx]) {
        return true;
      }
      tokenIdx++;
    }
  
    return false;
  }
docs: Returns true if the provided token was previously marked as removed.