gulp fails with error:

[shaunc]

$ node --version
v7.2.1

Shauns-MacBook-Pro:transducers.js shauncutts$ ./node_modules/.bin/gulp 
[16:40:20] Using gulpfile /Volumes/Macintosh_HD/Users/shauncutts/src/transducers.js/gulpfile.js
[16:40:20] Starting 'compile'...
[16:40:23] Finished 'compile' after 3.39 s
[16:40:23] Starting 'default'...
[16:40:23] Finished 'default' after 171 μs
error
stream.js:74
      throw er; // Unhandled stream error in pipe.
      ^

SyntaxError: [enforest] Unexpected token
454:     var [objIter, numsIter, brokenIter] = [obj, nums, broken].map(iterator);
             ^
    at expand$2 (/Volumes/Macintosh_HD/Users/shauncutts/src/transducers.js/node_modules/sweet.js/lib/sweet.js:90:27)
    at parse (/Volumes/Macintosh_HD/Users/shauncutts/src/transducers.js/node_modules/sweet.js/lib/sweet.js:123:29)
    at Object.compile (/Volumes/Macintosh_HD/Users/shauncutts/src/transducers.js/node_modules/sweet.js/lib/sweet.js:129:19)
    at Stream.<anonymous> (/Volumes/Macintosh_HD/Users/shauncutts/src/transducers.js/node_modules/gulp-sweetjs/index.js:47:23)
    at Stream.stream.write (/Volumes/Macintosh_HD/Users/shauncutts/src/transducers.js/node_modules/through/index.js:26:11)
    at DestroyableTransform.ondata (/Volumes/Macintosh_HD/Users/shauncutts/src/transducers.js/node_modules/through2/node_modules/readable-stream/lib/_stream_readable.js:541:20)
    at emitOne (events.js:96:13)
    at DestroyableTransform.emit (events.js:188:7)
    at readableAddChunk (/Volumes/Macintosh_HD/Users/shauncutts/src/transducers.js/node_modules/through2/node_modules/readable-stream/lib/_stream_readable.js:212:18)
    at DestroyableTransform.Readable.push (/Volumes/Macintosh_HD/Users/shauncutts/src/transducers.js/node_modules/through2/node_modules/readable-stream/lib/_stream_readable.js:171:10)