Troubleshooting: Why doesn't type inference fail here?

Question

Given a type declared as shown below

public class EqualityProbe<T>
{
  public EqualityProbe( Func<T> functionToGetActualValue, T expectedValue, string probeDescription) {..}

Client code:

// cannot infer bool here
new EqualityProbe(CanConnectToMachine, true, "Probe machine is online")
// compiles fine
new EqualityProbe<bool>(CanConnectToMachine, true, "Probe machine is online")

My understanding is that type-inference doesn't work for method groups (e.g. CanConnectToMachine) or anonymous methods (lambda expressions).
But in this case, why doesn't the compiler infer the type argument from the second argument

possible duplicate of [Why can't the C# constructor infer type?](http://stackoverflow.com/questions/3570167/why-cant-the-c-constructor-infer-type) — AakashM, Apr 20 '11 at 06:47
possible duplicate of [Why doesn't C# support implied generic types on class constructors?](http://stackoverflow.com/questions/45604/why-doesnt-c-sharp-support-implied-generic-types-on-class-constructors) — nawfal, May 27 '13 at 03:28

score 2 · Accepted Answer · edited May 23 '17 at 11:47

2

C# doesn't support type inference on constructors, although this can often be overcome through the use of a factory class.

See the answer here: Why can't the C# constructor infer type?

edited May 23 '17 at 11:47

Community

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answered Apr 20 '11 at 05:37

Iridium

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score 1 · Answer 2 · answered Apr 20 '11 at 06:03

1

Well, that how C# is ! It doenst infer for constructors. While instantiating a generic type, you need to specify the Type(s) that will be used for the generic ones.

answered Apr 20 '11 at 06:03

Dipti Mehta

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Troubleshooting: Why doesn't type inference fail here?

2 Answers2