Express C# generic type arguments more succinctly? -

inspired

comparing 2 collections equality irrespective of order of items in them

i created extension method test whether 2 collections equivalent. use extension method, have specify 2 type parameters this:

isequivalenttotesthelper<observablecollection<string>, string>(first, second, true); 

is there way implement extension method 1 generic constraint (e.g. observablecollection<string>) need specified?

update: posted modified code based on answers additional response question inspired one.

here's original code:

static public class enumerableextensions  {     static public bool isequivalentto<e,t>(this e first, e second) e : ienumerable<t>     {         if ((first == null) != (second == null))             return false;          if (!object.referenceequals(first, second) && (first != null))         {             if (first.count() != second.count())                 return false;              if ((first.count() != 0) && havemismatchedelement<e,t>(first, second))                 return false;         }          return true;     }      private static bool havemismatchedelement<e,t>(e first, e second) e : ienumerable<t>     {         int firstcount;         int secondcount;          var firstelementcounts = getelementcounts<e,t>(first, out firstcount);         var secondelementcounts = getelementcounts<e,t>(second, out secondcount);          if (firstcount != secondcount)             return true;          foreach (var kvp in firstelementcounts)         {             firstcount = kvp.value;             secondelementcounts.trygetvalue(kvp.key, out secondcount);              if (firstcount != secondcount)                 return true;         }          return false;     }      private static dictionary<t, int> getelementcounts<e,t>(e enumerable, out int nullcount) e : ienumerable<t>     {         var dictionary = new dictionary<t, int>();         nullcount = 0;          foreach (t element in enumerable)         {             if (element == null)             {                 nullcount++;             }             else             {                 int num;                 dictionary.trygetvalue(element, out num);                 num++;                 dictionary[element] = num;             }         }          return dictionary;     }      static private int gethashcode<e,t>(ienumerable<t> enumerable) e : ienumerable<t>     {         int hash = 17;          foreach (t val in enumerable.orderby(x => x))             hash = hash * 23 + val.gethashcode();          return hash;     } } 

static public bool isequivalentto<t>(this ienumerable<t> first, ienumerable<t> second)