javascript - ECMAScript 规范 : meaning of question mark in the spec

Question

我看到很多Let value be ?, Return ?规范中的某事。 example

谁知道?的意思。

Answer 1

来自 Algorithm Conventions ,

Abstract operations referenced using the functional application style and the method application style that are prefixed by ? indicate that ReturnIfAbrupt should be applied to the resulting Completion Record.

For example, ? operationName() is equivalent to ReturnIfAbrupt(operationName()).

Similarly, ? someValue.operationName() is equivalent to ReturnIfAbrupt(someValue.operationName()).