Python style lambda functions for Javascript

lambda.sjs

macro lambda {
	rule { $arg:ident: $stm:expr (,) ... } => { function($arg) {
		return $stm (,) ...;
	}}
	rule { $arg:ident (,) ...: $stm:expr (,) ...} => {function(x){
		var i = 0, $($arg = x[i++]) (,) ...;
		return $stm (,) ...;
	}}
}

/*
var y = [1,2,3];

y = y.map(lambda x: x+1);

var z = [[1,2],[2,3], [3,4]];

z = z.map(lambda x, y: x + y);

//becomes
console.log([1, 2, 3].map(function(a) {
  return a + 1;
}), [[1, 2], [2, 3], [3, 4]].map(function(a) {
  var b = 0, c = a[b++];
  a = a[b++];
  return c + a;
}));
*/