Hi all, I have been using the following line in calls to new aws.ec2.Instance(

subnetId: vpc.publicSubnetIds[0], // use the subnet(s) from awsx.ec2.Vpc

It works fine in 3 of my stacks with identical vpcs but on a new on it gives this error

Element implicitly has an 'any' type because expression of type '0' can't be used to index type 'Promise<Output<string>[]>'.
  Property '0' does not exist on type 'Promise<Output<string>[]>'.

I am baffled by it, if I copy index.ts to a new name it does not show the error. Any help greatly appreciated.

Are you getting this different behavior across different projects or different stacks of the same project? The AWSX output types did change a while back so I suspect you were on a previous version and updated recently. You need to use the publicSubnetIds output like this in the latest AWSX version:

subnetId: pulumi.output(vpc.publicSubnetIds.then(ids => ids[0])),

Same project, that code works so thank you but now I wonder why it works elsewhere

That is strange. Is this all on the same machine too? If so, it should be using the same

package-lock.json

to keep the stacks all on the same versions.

Yes, I wil dig deeper