code: function isPartOfDirectivePrologue(node) {
              const block = node.parent.parent;
  
              if (block.type !== "Program" && (block.type !== "BlockStatement" || !astUtils.isFunction(block.parent))) {
                  return false;
              }
  
              // Check the node is at a prologue.
              for (let i = 0; i < block.body.length; ++i) {
                  const statement = block.body[i];
  
                  if (statement === node.parent) {
                      return true;
                  }
                  if (!isDirective(statement)) {
                      break;
                  }
              }
  
              return false;
          }
docs: Checks whether or not a given node is a part of directive prologues.
  See also: http://www.ecma-international.org/ecma-262/6.0/#sec-directive-prologues-and-the-use-strict-directive
  @param {ASTNode} node - A node to check.
  @returns {boolean} Whether or not the node is a part of directive prologues.
  @private