help with macro

Created by: jlongster

I doubt this is a bug, but I'd like some help. I'm writing a macro that iterates through statements and will do stuff to them; for now, I'm just trying to get it to iterate through the statements.

macro _unroll {
    case ($stmt $rest ...) => {
        $stmt
        _unroll($rest ...)
    }
    case () => {
    }
}

macro async {
    case { $stmt ... } => {
        _unroll($stmt ...)
    }
}

async {
    var x = 5;
    var y = 5;    
}

This throws an error though:

/usr/local/lib/node_modules/sweet.js/lib/parser.js:3117
            throw e$320;
                  ^
Error: Line 112: Unexpected token ;
    at throwError (/usr/local/lib/node_modules/sweet.js/lib/parser.js:984:24)
    at throwUnexpected (/usr/local/lib/node_modules/sweet.js/lib/parser.js:1033:9)
    at expect (/usr/local/lib/node_modules/sweet.js/lib/parser.js:1038:13)
    at parsePrimaryExpression (/usr/local/lib/node_modules/sweet.js/lib/parser.js:1264:13)
    at parseLeftHandSideExpressionAllowCall (/usr/local/lib/node_modules/sweet.js/lib/parser.js:1382:56)
    at parsePostfixExpression (/usr/local/lib/node_modules/sweet.js/lib/parser.js:1414:24)
    at parseUnaryExpression (/usr/local/lib/node_modules/sweet.js/lib/parser.js:1469:16)
    at parseMultiplicativeExpression (/usr/local/lib/node_modules/sweet.js/lib/parser.js:1472:24)
    at parseAdditiveExpression (/usr/local/lib/node_modules/sweet.js/lib/parser.js:1484:24)
    at parseShiftExpression (/usr/local/lib/node_modules/sweet.js/lib/parser.js:1496:24)

What am I doing wrong?