| /* |
| 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. |
| */ |
| "use strict"; |
| |
| const READ = 0x1; |
| const WRITE = 0x2; |
| const RW = READ | WRITE; |
| |
| /** |
| * A Reference represents a single occurrence of an identifier in code. |
| * @class 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. |
| * @method Reference#isStatic |
| * @returns {boolean} static |
| */ |
| isStatic() { |
| return !this.tainted && this.resolved && this.resolved.scope.isStatic(); |
| } |
| |
| /** |
| * Whether the reference is writeable. |
| * @method Reference#isWrite |
| * @returns {boolean} write |
| */ |
| isWrite() { |
| return !!(this.flag & Reference.WRITE); |
| } |
| |
| /** |
| * Whether the reference is readable. |
| * @method Reference#isRead |
| * @returns {boolean} read |
| */ |
| isRead() { |
| return !!(this.flag & Reference.READ); |
| } |
| |
| /** |
| * Whether the reference is read-only. |
| * @method Reference#isReadOnly |
| * @returns {boolean} read only |
| */ |
| isReadOnly() { |
| return this.flag === Reference.READ; |
| } |
| |
| /** |
| * Whether the reference is write-only. |
| * @method Reference#isWriteOnly |
| * @returns {boolean} write only |
| */ |
| isWriteOnly() { |
| return this.flag === Reference.WRITE; |
| } |
| |
| /** |
| * Whether the reference is read-write. |
| * @method 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; |
| |
| module.exports = Reference; |
| |
| /* vim: set sw=4 ts=4 et tw=80 : */ |