mcs/tests/gtest-lambda-04.cs

   1
   2 //
   3 // This test is used to test the type information flow between arguments
   4 // in a generic method invocation, where:
   5 //
   6 //    1. We first infer the type of X from the first argument to F
   7 //
   8 //    2. We use this information to infer from the type of f1 and Func
   9 //       that X is a TimeSpan.
  10 //
  11 //    3. Use the X=String and Y=TimeSpan to infer the value for Z
  12 //       which is double
  13 //
  14
  15 using System;
  16 public delegate TResult Func<TArg0, TResult> (TArg0 arg0);
  17
  18 class Demo {
  19         static Z F<X,Y,Z>(X value, Func<X,Y> f1, Func<Y,Z> f2)
  20         {
  21                 return f2 (f1(value));
  22         }
  23         static int Main ()
  24         {
  25                 double d = F("1:15:30", s => TimeSpan.Parse(s), t => t.TotalSeconds);
  26                 if (d < 4529 || d > 4531)
  27                         return 1;
  28                 return 0;
  29         }
  30 }