Returns true if and only if there are any tokens or line comments between
start_token and end_token.
fn anythingBetween(tree: Ast, start_token: Ast.TokenIndex, end_token: Ast.TokenIndex) bool
fn anythingBetween(tree: Ast, start_token: Ast.TokenIndex, end_token: Ast.TokenIndex) bool {
if (start_token + 1 != end_token) return true;
return hasComment(tree, start_token, end_token);
}