Immutable JS OrderedMap: Insert a new entry after a given Key
问题 I have an Immutable OrderedMap as follows: pairs: Immutable.OrderedMap({"Key1":"Value1","Key2":"Value2","Key4":"Value4"}) I need to insert ["Key3":"Value3"] after ["Key2":"Value2"] dynamically. I thought pairs.MergeIn(['Key2'],OrderedMap({"Key3":"Value3"})) will serve the purpose but not working. I tried const newPairs=Immutable.OrderedMap(); newPairs.forEach(function(value,key,map)){ if(key=="Key4") newPairs.set('Key3','Value3') newPairs.set(key,value') }); But I know it's a stupid code