Why is the return type not considered when differentiating methods? [duplicate]

Question

Possible Duplicate:
Java - why no return type based method overloading?

The compiler does not consider return type when differentiating methods, so you cannot declare two methods with the same signature even if they have a different return type.
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Why is this?

Answer 1

Because it's not required to assign the result when you want to execute a method. How would the compiler then know which of the overloaded ones you'd like to call? There will be ambiguity.

Answer 2

Because you can't tell from just the method invocation what the return type is supposed to be. The compiler needs to be able to tell, using only information at the call site, what method to call. Return values may be discarded so you can't in general know that there is a return value and what its type is. it gets even more confusing once you start thinking about type coersions (short->int) or casts.

Basically when the compiler sees a method call it knows all of the arguments need to be there in order to be a valid method call, so it can use those arguments to find the right method to call. But returns values will not be known at the time of the call, and even the type of the return value may not be discoverable.