Confusing Error Message When Doc Comment inside Array

[Havvy]

Probably a few other places where it's also confusing.

Should probably state something like 'unexpected doc comment. A doc comment must precede an item`.

fn main() { let a = [1.0, 1.0 /** b */, 1.0]; }

<anon>:1:31: 1:39 error: expected one of `,`, `.`, or an operator, found `/** b */`
<anon>:1 fn main() { let a = [1.0, 1.0 /** b */, 1.0]; }
                                       ^~~~~~~~
playpen: application terminated with error code 101