On 11/16/2016 10:02 PM, Alex Buckley wrote:
- If you lex 'package', then the sequence must parse as the first alternative.
- If you don't lex 'package', but rather lex 'import', then parsing is
ambiguous until you've looked ahead to lex either 'open',
'module', or a keyword that can start TypeDeclaration. [Ignoring annotations
for simplicity.]
- If you lexed 'open' or module', then the sequence must parse as the second
alternative; if you lexed anything else, then the
sequence must parse as the first alternative.
I just tried this:
---8<---
import open.module;
module foo {
}
---8<---
According to lang-vm this should be legal. The import statement
contains restricted keywords in positions where they cannot be keywords.
=> Parsing should succeed.
javac rejects this, which supports your explanation that lexical lookahead
should suffice to recognize a ModuleDeclaration.
Which one will it be?
Stephan
