Allow top-level await

It seems like top-level await expressions are not allowed:

> espree.parse('await true')
Thrown:
{ [SyntaxError: Unexpected token true
] index: 6, lineNumber: 1, column: 7 }

Should they be enabled? One reason could be that there is a proposal for top-level await.

But actually my use case is when using ESLint inside Markdown files with eslint-plugin-markdown. Documentations might contain one liners that miss the context (i.e. the async function keyword) in order to be shorter.

For example let’s say I have a module dummy that returns a promise. I might want to document it like this:

`dummy` returns a promise and take an options object as argument:

``​`js
const returnValue = await dummy(options)
``​`

Acorn has a allowAwaitOutsideFunction option that does this.

[not-an-aardvark]

I’d be fine with adding a parser option for this which just passes through to the acorn option.

[mysticatea]

Thank you for this issue.

As README.md described, we support only stage 4 syntax in general: https://github.com/eslint/espree#how-do-you-determine-which-experimental-features-to-support

But Markdown use case sounds reasonable to me, and we don’t need any acorn plugins to implement this.

For now, I guess you can use babel-eslint.