107           var key = keys[i];
108           if (!undefinedOnly || obj[key] === void 0) obj[key] = source[key];
125   var property = function(key) {  argument
127       return obj == null ? void 0 : obj[key];
212     var key;  variable
214       key = _.findIndex(obj, predicate, context);
216       key = _.findKey(obj, predicate, context);
218     if (key !== void 0 && key !== -1) return obj[key];
282   _.pluck = function(obj, key) {  argument
283     return _.map(obj, _.property(key));
399         var key = iteratee(value, index, obj);
400         behavior(result, value, key);
408   _.groupBy = group(function(result, value, key) {  argument
409     if (_.has(result, key)) result[key].push(value); else result[key] = [value];
414   _.indexBy = group(function(result, value, key) {  argument
415     result[key] = value;
421   _.countBy = group(function(result, value, key) {  argument
422     if (_.has(result, key)) result[key]++; else result[key] = 1;
444     _.each(obj, function(value, key, obj) {  argument
445       (predicate(value, key, obj) ? pass : fail).push(value);
742     var i, length = arguments.length, key;
745       key = arguments[i];
746       obj[key] = _.bind(obj[key], obj);
753     var memoize = function(key) {  argument
755       var address = '' + (hasher ? hasher.apply(this, arguments) : key);
932     for (var key in obj) if (_.has(obj, key)) keys.push(key);
942     for (var key in obj) keys.push(key);
999     for (var key in obj) {
1000       if (_.isFunction(obj[key])) names.push(key);
1015     var keys = _.keys(obj), key;
1017       key = keys[i];
1018       if (predicate(obj[key], key, obj)) return key;
1031       iteratee = function(value, key, obj) { return key in obj; };  argument
1035       var key = keys[i];  variable
1036       var value = obj[key];
1037       if (iteratee(value, key, obj)) result[key] = value;
1048       iteratee = function(value, key) {  argument
1049         return !_.contains(keys, key);
1087       var key = keys[i];
1088       if (attrs[key] !== obj[key] || !(key in obj)) return false;
1171       var keys = _.keys(a), key;
1177         key = keys[length];
1178         if (!(_.has(b, key) && eq(a[key], b[key], aStack, bStack))) return false;
1267   _.has = function(obj, key) {  argument
1268     return obj != null && hasOwnProperty.call(obj, key);
1299     return obj == null ? function(){} : function(key) {
1300       return obj[key];