So, when is a good choice to not use strict mode? When you are running old (or third party) code that you haven’t had time to update yet. Strict mode is simply better. It isn’t on by default because it would break old code that was not written with it in mind.
The documentation says that the old runtime is based on Mozilla’s Rhino JavaScript interpreter which provides a subset of ECMAScript 5 and is based on 1.6, with a smattering of 1.7 and 1.8. The new Apps Script runtime is supported by the V8 runtime with few exceptions like E6 Modules.
It’s valid indeed. You’re allowed to wrap any simple assignment target in parenthesis. The left hand part of the = operation is a LeftHandSideExpression as you correctly identified. This can be tracked down through the various precendence levels (NewExpression, MemberExpression) to a PrimaryExpression, which in turn might be a CoverParenthesizedExpressionAndArrowParameterList: ( Expression[In, ?Yield] ) (actually, … Read more
Because it’s never been part of the standardized language. It wasn’t in the ECMAScript 1 or 2 specs at all, and only appears in ECMAScript 3 in Section B.2 (“Additional Properties”) (and subsequent editions in similar annexes through to today [ES2022 draft as of this writing]), which said:¹ Some implementations of ECMAScript have included additional properties for … Read more
I’m wondering if there is any way to get a value from a Promise or wait (block/sleep) until it has resolved, similar to .NET’s IAsyncResult.WaitHandle.WaitOne(). I know JavaScript is single-threaded, but I’m hoping that doesn’t mean that a function can’t yield. The current generation of Javascript in browsers does not have a wait() or sleep() … Read more