Promises Error Handling

promises-error-handling

var p = function () {
  var d = Q.defer();
  d.reject();
  return d.promise;
};

# Case 1
p()
  .then(function () {
    console.log('A');
  }, function () {
    console.log('B');
  });
//--> B


# Case 2
P()
  .then(function () {
    console.log('A');
  })
  .fail(function () {
    console.log('B');
  });
//--> B


# Case 3
p()
  .then(function () [
    console.log('A');
  })
  .fail(function () {
    console.log('B');
  })
  .then(function () {
    console.log('C');
  });
//--> B, C


# Case 4
p()
  .then(function () {
    console.log('A');
  })
  .fail(function () {
    console.log('B');
  })
  .fail(function () {
    console.log('C');
  })
  .then(function () {
    console.log('D');
  });
//--> B, D


# Case 5
p()
  .fail(function () {
    console.log('A');
  })
  .then(function () {
    console.log('B');
  })
  .fail(function () {
    console.log('C');
  })
  .then(function () {
    console.log('D')
  });
//--> A, B, D
  
  
# Case 6
p()
  .then(function () {
    console.log('A');
  })
  .then(function () {
    console.log('B');
  })
  .then(function () {
    console.log('C');
  })
  .fail(function () {
    console.log('D');
  });
//--> D