Sweet.js removes code from input

[are]

Sweet.js without any macros inside input file removes () from this code:

var m = new _DustObject3.default();

It becomes this:

var m = new _DustObject3.default;

Is this intentional?

[disnet]

Yep, it's intentional. When there are no arguments new doesn't need the parens so codegen will just omit them.