How to use the diff.DIFF_DELETE function in diff

} else if (mod[0] === diff_match_patch.DIFF_DELETE) {
                        var del_start = start_loc + index2;
                        var del_end = start_loc + this.dmp.diff_xIndex(diffs,
                                index1 + mod[1].length);
                        text = text.substring(0, del_start) + text.substring(del_end);
                        for (i = 0; i < offsets.length; i++) {
                            if (offsets[i] + nullPadding.length > del_start) {
                                if (offsets[i] + nullPadding.length < del_end) {
                                    offsets[i] = del_start - nullPadding.length;
                                } else {
                                    offsets[i] -= del_end - del_start;
                                }
                            }
                        }
                    }
                    if (mod[0] !== diff_match_patch.DIFF_DELETE) {
                        index1 += mod[1].length;
                    }
                }
            }
        }

        // Strip the padding off.
        text = text.substring(nullPadding.length, text.length - nullPadding.length);
        return text;
    },

} else if (mod[0] === diff_match_patch.DIFF_DELETE) {
                        var del_start = start_loc + index2;
                        var del_end = start_loc + this.dmp.diff_xIndex(diffs,
                                index1 + mod[1].length);
                        text = text.substring(0, del_start) + text.substring(del_end);
                        for (i = 0; i < offsets.length; i++) {
                            if (offsets[i] + nullPadding.length > del_start) {
                                if (offsets[i] + nullPadding.length < del_end) {
                                    offsets[i] = del_start - nullPadding.length;
                                } else {
                                    offsets[i] -= del_end - del_start;
                                }
                            }
                        }
                    }
                    if (mod[0] !== diff_match_patch.DIFF_DELETE) {
                        index1 += mod[1].length;
                    }
                }
            }
        }

        // Strip the padding off.
        text = text.substring(nullPadding.length, text.length - nullPadding.length);
        return text;
    },

} else if (mod[0] === diff_match_patch.DIFF_DELETE) {
                        var del_start = start_loc + index2;
                        var del_end = start_loc + this.dmp.diff_xIndex(diffs,
                                index1 + mod[1].length);
                        text = text.substring(0, del_start) + text.substring(del_end);
                        for (i = 0; i < offsets.length; i++) {
                            if (offsets[i] + nullPadding.length > del_start) {
                                if (offsets[i] + nullPadding.length < del_end) {
                                    offsets[i] = del_start - nullPadding.length;
                                } else {
                                    offsets[i] -= del_end - del_start;
                                }
                            }
                        }
                    }
                    if (mod[0] !== diff_match_patch.DIFF_DELETE) {
                        index1 += mod[1].length;
                    }
                }
            }
        }

        // Strip the padding off.
        text = text.substring(nullPadding.length, text.length - nullPadding.length);
        return text;
    },

case diff_match_patch.DIFF_EQUAL:
                        offset += region[1].length;
                        break;
                    case diff_match_patch.DIFF_INSERT:
                        var end = offset + region[1].length;
                        changes.push({
                            type: diff_match_patch.DIFF_INSERT,
                            start: session.convertOffsetToRowCol(offset),
                            end: session.convertOffsetToRowCol(end)
                        });
                        offset = end;
                        console.log("insert", region[1].length, " chars");
                        break;
                    case diff_match_patch.DIFF_DELETE:
                        changes.push({
                            type: diff_match_patch.DIFF_DELETE,
                            start: session.convertOffsetToRowCol(offset),
                            end: session.convertOffsetToRowCol(offset)
                        });
                        console.log("delete", region[1].length, " chars");
                        break;
                    default:
                        console.error("delta region with unknown type");
                    }
                });

delta.forEach(function(region) {
                    switch (region[0]) {
                    case diff_match_patch.DIFF_EQUAL:
                        offset += region[1].length;
                        break;
                    case diff_match_patch.DIFF_INSERT:
                        var end = offset + region[1].length;
                        changes.push({
                            type: diff_match_patch.DIFF_INSERT,
                            start: session.convertOffsetToRowCol(offset),
                            end: session.convertOffsetToRowCol(end)
                        });
                        offset = end;
                        console.log("insert", region[1].length, " chars");
                        break;
                    case diff_match_patch.DIFF_DELETE:
                        changes.push({
                            type: diff_match_patch.DIFF_DELETE,
                            start: session.convertOffsetToRowCol(offset),
                            end: session.convertOffsetToRowCol(offset)
                        });
                        console.log("delete", region[1].length, " chars");
                        break;
                    default:
                        console.error("delta region with unknown type");
                    }
                });

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @fileoverview This client-side code drives the synchronisation.
 * @author fraser@google.com (Neil Fraser)
 */

var server = require("plugins").getObject("server");

var diff_match_patch = require("diff");

var DIFF_EQUAL = diff_match_patch.DIFF_EQUAL;
var DIFF_DELETE = diff_match_patch.DIFF_DELETE;
var DIFF_INSERT = diff_match_patch.DIFF_INSERT;

/**
 * Singleton class containing all MobWrite code.
 */
var mobwrite = {};


/**
 * URL of Ajax gateway.
 * @type {string}
 */
mobwrite.syncGateway = '/mobwrite/';


/**

* distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @fileoverview This client-side code drives the synchronisation.
 * @author fraser@google.com (Neil Fraser)
 */

var server = require("bespin_server").server;
var diff_match_patch = require("diff");

var DIFF_EQUAL = diff_match_patch.DIFF_EQUAL;
var DIFF_DELETE = diff_match_patch.DIFF_DELETE;
var DIFF_INSERT = diff_match_patch.DIFF_INSERT;

/**
 * Singleton class containing all MobWrite code.
 */
var mobwrite = {};


/**
 * URL of Ajax gateway.
 * @type {string}
 */
mobwrite.syncGateway = '/mobwrite/';


/**

var index2;
                var i;
                for (var y = 0; y < patches[x].diffs.length; y++) {
                    var mod = patches[x].diffs[y];
                    if (mod[0] !== diff_match_patch.DIFF_EQUAL) {
                        index2 = this.shareObj.dmp.diff_xIndex(diffs, index1);
                    }
                    if (mod[0] === diff_match_patch.DIFF_INSERT) {
                        text = text.substring(0, start_loc + index2) + mod[1] +
                                     text.substring(start_loc + index2);
                        for (i = 0; i < offsets.length; i++) {
                            if (offsets[i] + nullPadding.length > start_loc + index2) {
                                offsets[i] += mod[1].length;
                            }
                        }
                    } else if (mod[0] === diff_match_patch.DIFF_DELETE) {
                        var del_start = start_loc + index2;
                        var del_end = start_loc + this.shareObj.dmp.diff_xIndex(diffs,
                                index1 + mod[1].length);
                        text = text.substring(0, del_start) + text.substring(del_end);
                        for (i = 0; i < offsets.length; i++) {
                            if (offsets[i] + nullPadding.length > del_start) {
                                if (offsets[i] + nullPadding.length < del_end) {
                                    offsets[i] = del_start - nullPadding.length;
                                } else {
                                    offsets[i] -= del_end - del_start;
                                }
                            }
                        }
                    }
                    if (mod[0] !== diff_match_patch.DIFF_DELETE) {
                        index1 += mod[1].length;