| // Copyright 2014 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| "use strict"; |
| |
| var callSiteCache = new $Map; |
| |
| function SameCallSiteElements(rawStrings, other) { |
| var length = rawStrings.length; |
| var other = other.raw; |
| |
| if (length !== other.length) return false; |
| |
| for (var i = 0; i < length; ++i) { |
| if (rawStrings[i] !== other[i]) return false; |
| } |
| |
| return true; |
| } |
| |
| |
| function GetCachedCallSite(siteObj, hash) { |
| var obj = %MapGet(callSiteCache, hash); |
| |
| if (IS_UNDEFINED(obj)) return; |
| |
| var length = obj.length; |
| for (var i = 0; i < length; ++i) { |
| if (SameCallSiteElements(siteObj, obj[i])) return obj[i]; |
| } |
| } |
| |
| |
| function SetCachedCallSite(siteObj, hash) { |
| var obj = %MapGet(callSiteCache, hash); |
| var array; |
| |
| if (IS_UNDEFINED(obj)) { |
| array = new InternalArray(1); |
| array[0] = siteObj; |
| %MapSet(callSiteCache, hash, array); |
| } else { |
| obj.push(siteObj); |
| } |
| |
| return siteObj; |
| } |
| |
| |
| function GetTemplateCallSite(siteObj, rawStrings, hash) { |
| var cached = GetCachedCallSite(rawStrings, hash); |
| |
| if (!IS_UNDEFINED(cached)) return cached; |
| |
| %AddNamedProperty(siteObj, "raw", %ObjectFreeze(rawStrings), |
| READ_ONLY | DONT_ENUM | DONT_DELETE); |
| |
| return SetCachedCallSite(%ObjectFreeze(siteObj), hash); |
| } |
| |
| |
| // ES6 Draft 10-14-2014, section 21.1.2.4 |
| function StringRaw(callSite) { |
| // TODO(caitp): Use rest parameters when implemented |
| var numberOfSubstitutions = %_ArgumentsLength(); |
| var cooked = ToObject(callSite); |
| var raw = ToObject(cooked.raw); |
| var literalSegments = ToLength(raw.length); |
| if (literalSegments <= 0) return ""; |
| |
| var result = ToString(raw[0]); |
| |
| for (var i = 1; i < literalSegments; ++i) { |
| if (i < numberOfSubstitutions) { |
| result += ToString(%_Arguments(i)); |
| } |
| result += ToString(raw[i]); |
| } |
| |
| return result; |
| } |
| |
| |
| function ExtendStringForTemplates() { |
| %CheckIsBootstrapping(); |
| |
| // Set up the non-enumerable functions on the String object. |
| InstallFunctions($String, DONT_ENUM, $Array( |
| "raw", StringRaw |
| )); |
| } |
| |
| ExtendStringForTemplates(); |