Hi I have a question regarding method sets. In the code below I understand why line 30 gives a compilation error (variable has value semantics so cant really user pointer semantics etc). However I don’t quite understand why line 29 doesn’t throw an error. Why does the language permit calling a method with a reference of *T on a variable of type T? Code is as per below.
Hi @Sarabjit_Bhatia ,
Why does the language permit calling a method with a reference of *T on a variable of type T?
This is possible because methods with a pointer receiver are also bound to the pointer’s base type. (See Method declrarations in the Go spec.)
In other words, the dot operator in
u.notify()
accepts a pointer as well as a non-pointer on the left side.
sendNotification(u), on the other hand, has interface semantics that work differently.
This call
sendNotification(u)
fails because sendNotification() expects an interface with method notify(). Only pointer types can implement this interface, because method notify() has a pointer receiver. Hence sendNotification(u) complains because uis a non-pointeruservalue, butsendNotification(&u)` works fine. (See Method sets in the spec).
Thanks a lot for help!
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