code: function Reference(ident, scope, flag,writeExpr, maybeImplicitGlobal, partial, init) {
        /**
         * Identifier syntax node.
         * @member {esprima#Identifier} Reference#identifier
         */
        this.identifier = ident;
        /**
         * Reference to the enclosing Scope.
         * @member {Scope} Reference#from
         */
        this.from = scope;
        /**
         * Whether the reference comes from a dynamic scope (such as 'eval',
         * 'with', etc.), and may be trapped by dynamic scopes.
         * @member {boolean} Reference#tainted
         */
        this.tainted = false;
        /**
         * The variable this reference is resolved with.
         * @member {Variable} Reference#resolved
         */
        this.resolved = null;
        /**
         * The read-write mode of the reference. (Value is one of {@link
         * Reference.READ}, {@link Reference.RW}, {@link Reference.WRITE}).
         * @member {number} Reference#flag
         * @private
         */
        this.flag = flag;
        if (this.isWrite()) {
            /**
             * If reference is writeable, this is the tree being written to it.
             * @member {esprima#Node} Reference#writeExpr
             */
            this.writeExpr = writeExpr;
            /**
             * Whether the Reference might refer to a partial value of writeExpr.
             * @member {boolean} Reference#partial
             */
            this.partial = partial;
            /**
             * Whether the Reference is to write of initialization.
             * @member {boolean} Reference#init
             */
            this.init = init;
        }
        this.__maybeImplicitGlobal = maybeImplicitGlobal;
    }
docs: A Reference represents a single occurrence of an identifier in code.
  @class Reference