2017 update: First, for readers coming today – here is a version that works with Node 7 (4+): function enforceFastProperties(o) { function Sub() {} Sub.prototype = o; var receiver = new Sub(); // create an instance function ic() { return typeof receiver.foo; } // perform access ic(); ic(); return o; eval(“o” + o); // ensure … Read more
Try: var g = f(); // this question is over this value. g.next(); // returns: { value: 1, done: false } g.next(123); // returns: { value: 2, done: false } g.next(456); // returns: { value: [123, 456], done: true }
Thanks a lot to @dan-abramov as his comment is the answer! (Give him the vote up in case you come across this). You can just put e.g. node –max_old_space_size=4096 node_modules/.bin/react-scripts start in there instead of react-scripts start
The DOM is the DOM, and the JavaScript implementation is simply a separate entity. The DOM represents a set of facilities that a web browser exposes to the JavaScript environment. There’s no requirement however that any particular JavaScript runtime will have any facilities exposed via the global object. What Node.js is is a stand-alone JavaScript … Read more
The answer, for now, is no. The [[FunctionLocation]] property you see in Inspector is added in V8Debugger::internalProperties() in the debugger’s C++ code, which uses another C++ function V8Debugger::functionLocation() to gather information about the function. functionLocation() then uses a number of V8-specific C++ APIs such as v8::Function::GetScriptLineNumber() and GetScriptColumnNumber() to find out the exact information. All … Read more
In V8 null, undefined, true and false internally are heap allocated objects. If you are comming from Java you can say that true and false in V8 are more like Boolean.TRUE and Boolean.FALSE in Java. There is an important difference between real local variables and variables that are captured by closures or shadowed by eval/with. … Read more
A nice write-up of the reasoning behind this can be found in this article by Mohsen Azimi. Here’s a quick summary of it. The following keywords are defined in the JavaScript spec as FutureReservedWord: implements interface let package private protected public static yield In normal mode, these can be used as variable names without errors; … Read more
I don’t know how to invoke the disassembler from C++ code, but there is a quick-and-dirty way to get a disassembly from the shell. First, compile v8 with disassembler support: scons [your v8 build options here] disassembler=on sample=shell Now you can invoke the shell with the “–print_code” option: ./shell –print_code hello.js Which should give you … Read more
There is a chromium bug open for this: Issue 604033 – JIT compiler not preserving method behavior So yes It’s just a bug!
I realize that this may not be an exact answer to your question, but I figured I would put my 2 cents worth in as I doubt to many people have tried this. I got it to work by created a managed wrapper using mixed mode C++. There are other ways to do it, but … Read more