Sweet $q Promise methods for IE8

ie8_$q.sjs

/**
 * Macros to make $q Promises better in IE8
 * 
 * Tested with v0.6.0 of sweet.js
 */

/**
 * These operator macros will take `.catch` and `.finally` method invocations
 * and transform them into IE8 safe variants.
 */
operator (.catch) 1 left
  { $base, $exp } => #{ $base['catch']($exp) }

operator (.finally) 1 left
  { $base, $exp } => #{ $base['finally']($exp) }


/**
 * Example code
 */
promise
.then(function(res) {
  return res.data;
})
.catch(function(err) {
  console.log(err);
})
.finally(function(){
  console.log('Finally!');
});


/**
 * Transforms to this
 */
promise.then(function (res) {
    return res.data;
})['catch'](function (err) {
    console.log(err);
})['finally'](function () {
    console.log('Finally!');
});

This still has problems when a .then is inserted in between the .catch and .finally in the chain.

This:

promise.catch(function(err) {
  console.log(err);
})
.then(function(res) {
  return res.data;
})
.finally(function(){
  console.log('Finally!');
});

ends up compiling to:

promise['catch'](function (err) {
    console.log(err);
}.then(function (res) {
    return res.data;
}))['finally'](function () {
    console.log('Finally!');
});

I've tried messing around with different levels of precedence, but to no avail.