167 lines
		
	
	
		
			4.7 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			167 lines
		
	
	
		
			4.7 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| /*
 | |
|   Copyright (C) 2015 Yusuke Suzuki <utatane.tea@gmail.com>
 | |
| 
 | |
|   Redistribution and use in source and binary forms, with or without
 | |
|   modification, are permitted provided that the following conditions are met:
 | |
| 
 | |
|     * Redistributions of source code must retain the above copyright
 | |
|       notice, this list of conditions and the following disclaimer.
 | |
|     * Redistributions in binary form must reproduce the above copyright
 | |
|       notice, this list of conditions and the following disclaimer in the
 | |
|       documentation and/or other materials provided with the distribution.
 | |
| 
 | |
|   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 | |
|   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 | |
|   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 | |
|   ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
 | |
|   DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 | |
|   (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 | |
|   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 | |
|   ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 | |
|   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 | |
|   THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 | |
| */
 | |
| 
 | |
| const READ = 0x1;
 | |
| const WRITE = 0x2;
 | |
| const RW = READ | WRITE;
 | |
| 
 | |
| /**
 | |
|  * A Reference represents a single occurrence of an identifier in code.
 | |
|  * @constructor Reference
 | |
|  */
 | |
| class Reference {
 | |
|     constructor(ident, scope, flag, writeExpr, maybeImplicitGlobal, partial, init) {
 | |
| 
 | |
|         /**
 | |
|          * Identifier syntax node.
 | |
|          * @member {espreeIdentifier} 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 {espreeNode} 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;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Whether the reference is static.
 | |
|      * @function Reference#isStatic
 | |
|      * @returns {boolean} static
 | |
|      */
 | |
|     isStatic() {
 | |
|         return !this.tainted && this.resolved && this.resolved.scope.isStatic();
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Whether the reference is writeable.
 | |
|      * @function Reference#isWrite
 | |
|      * @returns {boolean} write
 | |
|      */
 | |
|     isWrite() {
 | |
|         return !!(this.flag & Reference.WRITE);
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Whether the reference is readable.
 | |
|      * @function Reference#isRead
 | |
|      * @returns {boolean} read
 | |
|      */
 | |
|     isRead() {
 | |
|         return !!(this.flag & Reference.READ);
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Whether the reference is read-only.
 | |
|      * @function Reference#isReadOnly
 | |
|      * @returns {boolean} read only
 | |
|      */
 | |
|     isReadOnly() {
 | |
|         return this.flag === Reference.READ;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Whether the reference is write-only.
 | |
|      * @function Reference#isWriteOnly
 | |
|      * @returns {boolean} write only
 | |
|      */
 | |
|     isWriteOnly() {
 | |
|         return this.flag === Reference.WRITE;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Whether the reference is read-write.
 | |
|      * @function Reference#isReadWrite
 | |
|      * @returns {boolean} read write
 | |
|      */
 | |
|     isReadWrite() {
 | |
|         return this.flag === Reference.RW;
 | |
|     }
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * @constant Reference.READ
 | |
|  * @private
 | |
|  */
 | |
| Reference.READ = READ;
 | |
| 
 | |
| /**
 | |
|  * @constant Reference.WRITE
 | |
|  * @private
 | |
|  */
 | |
| Reference.WRITE = WRITE;
 | |
| 
 | |
| /**
 | |
|  * @constant Reference.RW
 | |
|  * @private
 | |
|  */
 | |
| Reference.RW = RW;
 | |
| 
 | |
| export default Reference;
 | |
| 
 | |
| /* vim: set sw=4 ts=4 et tw=80 : */
 |