AJAX (EXTjs)

Alguém sabe me explicar o que é isso, quero dizer debugar cada linha, por exemplo o q ´eo o form, o…:

success: function(form, o) { obj = Ext.util.JSON.decode(o.response.responseText); if (obj.failed == '0' && obj.uploaded != '0') { Ext.Msg.alert('Success', 'All files uploaded'); } else if (obj.uploaded == '0') { Ext.Msg.alert('Success', 'Nothing Uploaded'); } else { Ext.Msg.alert('Success', obj.uploaded + ' files uploaded <br/>' + obj.failed + ' files failed to upload'); } panelRightTop.getForm().reset(); store.load(); } });

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