It would be convenient to support [ES6 default parameters](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Default_parameters) in WebPPL. So `function(x){var x = (x=='undefined' ? 1 : x);...}` becomes `function(x=1){...}`. This could happen with #2, if we ever do that!
It would be convenient to support ES6 default parameters in WebPPL.
So
function(x){var x = (x=='undefined' ? 1 : x);...}becomesfunction(x=1){...}.This could happen with #2, if we ever do that!