How to use the alloy/underscore._.isFunction function in alloy

_.isFunction(params.success) && params.success(resp);
			} else {
				// error or offline - save & use local data

				// save data locally when server returned an error
				if (!_response.localOnly && params.disableSaveDataLocallyOnServerError) {
					params.returnErrorResponse && _.isFunction(params.error) && params.error(_response);
					logger(DEBUG, "NOTICE: The data is not being saved locally");
				} else {
					resp = saveData();
					if (_.isUndefined(_response.offline)) {
						// error
						_.isFunction(params.error) && params.error(params.returnErrorResponse ? _response : resp);
					} else {
						//offline - still a data success
						_.isFunction(params.success) && params.success(resp);
					}
				}
			}
		});
		break;

else if (method === 'create' || method === 'update') {
		if (!model.id) {
			model.id = guid();
			model.set(model.idAttribute, model.id);
		}
		TAP.setObject(prefix + '-' + model.id, model.toJSON() || {});
		resp = model.toJSON();
	} else if (method === 'delete') {
		TAP.removeProperty(prefix + '-' + model.id);
		model.clear();
		resp = model.toJSON();
	}

	// process success/error handlers, if present
	if (resp) {
        if (_.isFunction(opts.success)) { opts.success(resp); }
        if (method === "read") { model.trigger("fetch"); }
    } else {
		if (_.isFunction(opts.error)) { opts.error(resp); }
    }
}

model.set(model.idAttribute, model.id);
		}
		TAP.setObject(prefix + '-' + model.id, model.toJSON() || {});
		resp = model.toJSON();
	} else if (method === 'delete') {
		TAP.removeProperty(prefix + '-' + model.id);
		model.clear();
		resp = model.toJSON();
	}

	// process success/error handlers, if present
	if (resp) {
        if (_.isFunction(opts.success)) { opts.success(resp); }
        if (method === "read") { model.trigger("fetch"); }
    } else {
		if (_.isFunction(opts.error)) { opts.error(resp); }
    }
}

} else direction = 1;
    db = Ti.Database.open(config.adapter.db_name);
    migrator.db = db;
    db.execute("BEGIN;");
    if (migrations.length) for (var i = 0; migrations.length > i; i++) {
        var migration = migrations[i], context = {};
        migration(context);
        if (direction) {
            if (context.id > targetNumber) break;
            if (currentNumber >= context.id) continue;
        } else {
            if (targetNumber >= context.id) break;
            if (context.id > currentNumber) continue;
        }
        var funcName = direction ? "up" : "down";
        _.isFunction(context[funcName]) && context[funcName](migrator);
    } else migrator.createTable(config);
    db.execute("DELETE FROM migrations where model = ?", config.adapter.collection_name);
    db.execute("INSERT INTO migrations VALUES (?,?)", targetNumber, config.adapter.collection_name);
    db.execute("COMMIT;");
    db.close();
    migrator.db = null;
}

};
    var config = (model ? model.prototype.config : {}) || {};
    var mod;
    if (config.adapter && config.adapter.type) {
        mod = require("alloy/sync/" + config.adapter.type);
        extendObj.sync = function(method, model, opts) {
            mod.sync(method, model, opts);
        };
    } else extendObj.sync = function(method, model) {
        Ti.API.warn("Execution of " + method + "#sync() function on a collection that does not support persistence");
        Ti.API.warn("model: " + JSON.stringify(model.toJSON()));
    };
    var Collection = Backbone.Collection.extend(extendObj);
    Collection.prototype.config = config;
    _.isFunction(modelDesc.extendCollection) && (Collection = modelDesc.extendCollection(Collection) || Collection);
    mod && _.isFunction(mod.afterCollectionCreate) && mod.afterCollectionCreate(Collection);
    return Collection;
};

model: model
    };
    var config = (model ? model.prototype.config : {}) || {};
    var mod;
    if (config.adapter && config.adapter.type) {
        mod = require("alloy/sync/" + config.adapter.type);
        extendObj.sync = function(method, model, opts) {
            return mod.sync(method, model, opts);
        };
    } else extendObj.sync = function(method, model) {
        Ti.API.warn("Execution of " + method + "#sync() function on a collection that does not support persistence");
        Ti.API.warn("model: " + JSON.stringify(model.toJSON()));
    };
    var Collection = Backbone.Collection.extend(extendObj);
    Collection.prototype.config = config;
    _.isFunction(modelDesc.extendCollection) && (Collection = modelDesc.extendCollection(Collection) || Collection);
    mod && _.isFunction(mod.afterCollectionCreate) && mod.afterCollectionCreate(Collection);
    return Collection;
};

db.close();
            return model.toJSON();
        }();
        break;

      case "read":
        var sql = opts.query || "SELECT * FROM " + table;
        db = Ti.Database.open(dbName);
        var rs;
        rs = _.isString(sql) ? db.execute(sql) : db.execute(sql.statement, sql.params);
        var len = 0;
        var values = [];
        while (rs.isValidRow()) {
            var o = {};
            var fc = 0;
            fc = _.isFunction(rs.fieldCount) ? rs.fieldCount() : rs.fieldCount;
            _.times(fc, function(c) {
                var fn = rs.fieldName(c);
                o[fn] = rs.fieldByName(fn);
            });
            values.push(o);
            len++;
            rs.next();
        }
        rs.close();
        db.close();
        model.length = len;
        resp = 1 === len ? values[0] : values;
        break;

      case "delete":
        var sql = "DELETE FROM " + table + " WHERE " + model.idAttribute + "=?";

db = Ti.Database.open(config.adapter.db_name);
    migrator.db = db;
    db.execute("BEGIN;");
    if (migrations.length) for (var i = 0; i < migrations.length; i++) {
        var migration = migrations[i];
        var context = {};
        migration(context);
        if (direction) {
            if (context.id > targetNumber) break;
            if (context.id <= currentNumber) continue;
        } else {
            if (context.id <= targetNumber) break;
            if (context.id > currentNumber) continue;
        }
        var funcName = direction ? "up" : "down";
        _.isFunction(context[funcName]) && context[funcName](migrator);
    } else migrator.createTable(config);
    db.execute("DELETE FROM migrations where model = ?", config.adapter.collection_name);
    db.execute("INSERT INTO migrations VALUES (?,?)", targetNumber, config.adapter.collection_name);
    db.execute("COMMIT;");
    db.close();
    migrator.db = null;
}

model: model
    };
    var config = (model ? model.prototype.config : {}) || {};
    var mod;
    if (config.adapter && config.adapter.type) {
        mod = require("alloy/sync/" + config.adapter.type);
        extendObj.sync = function(method, model, opts) {
            mod.sync(method, model, opts);
        };
    } else extendObj.sync = function(method, model) {
        Ti.API.warn("Execution of " + method + "#sync() function on a collection that does not support persistence");
        Ti.API.warn("model: " + JSON.stringify(model.toJSON()));
    };
    var Collection = Backbone.Collection.extend(extendObj);
    Collection.prototype.config = config;
    _.isFunction(modelDesc.extendCollection) && (Collection = modelDesc.extendCollection(Collection) || Collection);
    mod && _.isFunction(mod.afterCollectionCreate) && mod.afterCollectionCreate(Collection);
    return Collection;
};

function parseJSON(_response, parentNode) {
    var data = _response.responseJSON;
    if (!_.isUndefined(parentNode)) {
      data = _.isFunction(parentNode) ? parentNode(data, opts) : traverseProperties(data, parentNode);
    }
    logger(DEBUG, "server response: ", data);
    return data;
  }