for await 给出 SyntaxError: Unexpected reserved word inside a async function

Question

Here is my code that throws the exception. Not able to figure out why it says 'Unexpected reserved word'. main() function is an async type. It isn't complaining for above line of code.

const { BlobServiceClient } = require("@azure/storage-blob");
async function main() {
    try {
        const blobServiceClient = await BlobServiceClient.fromConnectionString('some string');
        let i = 1;
        const result = await blobServiceClient.listContainers();
        for await (const container of result) {
            console.log(`Container ${i++}: ${container.name}`);
        }
    } catch (error) {
        console.log(error);
    }
}

main();

Answer 1

Your are getting this error because your Node version is lower than 10.0 and doesn't support for await...of . As a side note, for await has no effect here and can be substituted for just for Turns out api does need it

---

added: from the docs : you can either use for await of if your runtime supports it, or iterate an iterable in an old-fashioned way

let containerItem = await result.next();
while (!containerItem.done) {
  console.log(`Container ${i++}: ${containerItem.value.name}`);
  containerItem = await iter.next();
}

Answer 2

There is an work around for this one:

const { BlobServiceClient } = require("@azure/storage-blob");

async function main() {
    try {
        const blobServiceClient = await BlobServiceClient.fromConnectionString('DefaultEndpointsProtocol=https;AccountName=devappsstorage;AccountKey=aw/FF01OIfnYmK6Bh+d4NIhvVBaDKn942O22YAMNycX/27qKVwYW+/Dma/C7pI+lvU0wpo/VBJ1jFd4yi3MMWw==;EndpointSuffix=core.windows.net');
        let i = 1;
        let iter = blobServiceClient.listContainers();
        let containerItem = await iter.next();
        while (!containerItem.done) {
            console.log(`Container ${i++}: ${containerItem.value.name}`);
            containerItem = await iter.next();
          }
    } catch (error) {
        console.log(error);
    }
}

main();