First token:
pos := p.expect(token.PACKAGE)
https://github.com/golang/go/blob/master/src/go/parser/parser.go#L2854
More on recursive descent parser.
First token:
pos := p.expect(token.PACKAGE)
https://github.com/golang/go/blob/master/src/go/parser/parser.go#L2854
More on recursive descent parser.