Require types to be declared at the top of the file (after import)

[gajus]

Please describe what the rule should do:

Require that all type declarations appear at the top of the file, first thing after any import declarations.

What category of rule is this? (place an "X" next to just one item)

[x] Enforces code style
[ ] Warns about a potential error
[ ] Suggests an alternate way of doing something
[ ] Other (please specify:)

Provide 2-3 code examples that this rule will warn about:

Good:

import createAsyncTracker from '../createAsyncTracker';
import type {
  AdType
} from '../types';

type Unit = {|
  prefix: string,
  ignoreSuffix?: Array<string>,
  size: string,
  id: string,
  max?: number
|};

Bad:

import createAsyncTracker from '../createAsyncTracker';
import type {
  AdType
} from '../types';

const foo = 'bar';

type Unit = {|
  prefix: string,
  ignoreSuffix?: Array<string>,
  size: string,
  id: string,
  max?: number
|};

[gajus]

@danharper Might be a good idea to create an issue template, like ESLint does:

• http://eslint.org/docs/developer-guide/contributing/new-rules
• https://raw.githubusercontent.com/eslint/eslint/master/templates/rule-proposal.md

Do you want me to create one?

Is the above information sufficient? (This issue)

[danharper]

👍 on an issue template