public static System.Collections.Immutable.IImmutableDictionary <T1, T2> Merge <T1, T2>(this System.Collections.Immutable.IImmutableDictionary <T1, T2> first, System.Collections.Immutable.IImmutableDictionary <T1, T2> second)
where T2 : IMergeable <T2>
{
var newDict = first.ToDictionary(x => x.Key, x => x.Value);
foreach (var other in second)
{
T2 set;
if (newDict.TryGetValue(other.Key, out set))
{
set = set.Merge(other.Value);
newDict[other.Key] = set;
}
else
{
newDict.Add(other.Key, other.Value);
}
}
return(ImmutableDictionary <T1, T2> .Empty.AddRange(newDict));
}