type assertion

main.go

package main

import "fmt"

type ConcreteTypeTypeReceiver struct {n int}
func (c ConcreteTypeTypeReceiver) someMethod() int {return c.n}

// declaration above SUPPORTs the following types 
//    1. `ConcreteTypeTypeReceiver` - with methods (according to case C2)
//       1. `someMethod()`
//    2. `*ConcreteTypeTypeReceiver` - with methods (according to case F2)
//       1. `someMethod()`

type ConcreteTypePtrReceiver struct {n int}
func (c *ConcreteTypePtrReceiver) someMethod() int {return c.n}

// declaration above DOS NOT SUPPORT the following types 
//    1. `ConcreteTypePtrReceiver` - with methods (according to case I2)
//       1. `someMethod()`

// declaration above SUPPORTs the following types 
//    1. `*ConcreteTypePtrReceiver` - with methods (according to case L2)
//       1. `someMethod()`

type InterfaceType interface {
	someMethod() int
}

func main() {
	fmt.Printf("--== Concrete Type with Type Method Receiver; Interface Dynamic Value is Value ==--\n")
	{ var x interface{} =    ConcreteTypeTypeReceiver{1};  fmt.Printf("A1: %#v %T; ", x, x); var y  ConcreteTypeTypeReceiver = x.(ConcreteTypeTypeReceiver);   fmt.Printf("%#v %T\n", y, y) } // A1: {1} main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver; {1} main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver
	{ var x InterfaceType =  ConcreteTypeTypeReceiver{1};  fmt.Printf("A2: %#v %T; ", x, x); var y  ConcreteTypeTypeReceiver = x.(ConcreteTypeTypeReceiver);   fmt.Printf("%#v %T\n", y, y) } // A2: {1} main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver; {1} main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver

//	{ var x interface{} =    ConcreteTypeTypeReceiver{1};  fmt.Printf("B1: %#v %T; ", x, x); var y *ConcreteTypeTypeReceiver = x.(*ConcreteTypeTypeReceiver);  fmt.Printf("%#v %T\n", y, y) } // B1: {1} main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver; panic: interface conversion: interface {}       is main.ConcreteTypeTypeReceiver, not *main.ConcreteTypeTypeReceiver
//	{ var x InterfaceType =  ConcreteTypeTypeReceiver{1};  fmt.Printf("B2: %#v %T; ", x, x); var y *ConcreteTypeTypeReceiver = x.(*ConcreteTypeTypeReceiver);  fmt.Printf("%#v %T\n", y, y) } // B2: {1} main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver; panic: interface conversion: main.InterfaceType is main.ConcreteTypeTypeReceiver, not *main.ConcreteTypeTypeReceiver

	{ var x interface{} =    ConcreteTypeTypeReceiver{1};  fmt.Printf("C1: %#v %T; ", x, x); var y  InterfaceType = x.(InterfaceType);                         fmt.Printf("%#v %T\n", y, y) } // C1: {1} main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver; {1} main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver
	{ var x InterfaceType =  ConcreteTypeTypeReceiver{1};  fmt.Printf("C2: %#v %T; ", x, x); var y  InterfaceType = x.(InterfaceType);                         fmt.Printf("%#v %T\n", y, y) } // C2: {1} main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver; {1} main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver

	fmt.Println()
	fmt.Printf("--== Concrete Type with Type Method Receiver; Interface Dynamic Value is Pointer ==--\n")
//	{ var x interface{} =   &ConcreteTypeTypeReceiver{1};  fmt.Printf("D1: %#v %T; ", x, x); var y  ConcreteTypeTypeReceiver = x.(ConcreteTypeTypeReceiver);   fmt.Printf("%#v %T\n", y, y) } // D1: &{1} &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver; panic: interface conversion: interface {}       is *main.ConcreteTypeTypeReceiver, not main.ConcreteTypeTypeReceiver
//	{ var x InterfaceType = &ConcreteTypeTypeReceiver{1};  fmt.Printf("D2: %#v %T; ", x, x); var y  ConcreteTypeTypeReceiver = x.(ConcreteTypeTypeReceiver);   fmt.Printf("%#v %T\n", y, y) } // D2: &{1} &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver; panic: interface conversion: main.InterfaceType is *main.ConcreteTypeTypeReceiver, not main.ConcreteTypeTypeReceiver

	{ var x interface{} =   &ConcreteTypeTypeReceiver{1};  fmt.Printf("E1: %#v %T; ", x, x); var y *ConcreteTypeTypeReceiver = x.(*ConcreteTypeTypeReceiver);  fmt.Printf("%#v %T\n", y, y) } // E1: &{1} &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver; &{1} &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver
	{ var x InterfaceType = &ConcreteTypeTypeReceiver{1};  fmt.Printf("E2: %#v %T; ", x, x); var y *ConcreteTypeTypeReceiver = x.(*ConcreteTypeTypeReceiver);  fmt.Printf("%#v %T\n", y, y) } // E2: &{1} &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver; &{1} &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver

	{ var x interface{} =   &ConcreteTypeTypeReceiver{1};  fmt.Printf("F1: %#v %T; ", x, x); var y  InterfaceType = x.(InterfaceType);                         fmt.Printf("%#v %T\n", y, y) } // F1: &{1} &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver; &{1} &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver
	{ var x InterfaceType = &ConcreteTypeTypeReceiver{1};  fmt.Printf("F2: %#v %T; ", x, x); var y  InterfaceType = x.(InterfaceType);                         fmt.Printf("%#v %T\n", y, y) } // F2: &{1} &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver; &{1} &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver

	fmt.Println()
	fmt.Printf("--== Concrete Type with Pointer Method Receiver; Interface Dynamic Value is Value ==--\n")
	{ var x interface{} =    ConcreteTypePtrReceiver{1};   fmt.Printf("G1: %#v %T; ", x, x); var y  ConcreteTypePtrReceiver = x.(ConcreteTypePtrReceiver);     fmt.Printf("%#v %T\n", y, y) } // G1: {1} main.ConcreteTypePtrReceiver{n:1} main.ConcreteTypePtrReceiver; {1} main.ConcreteTypePtrReceiver{n:1} main.ConcreteTypePtrReceiver
//	{ var x InterfaceType =  ConcreteTypePtrReceiver{1};   fmt.Printf("G2: %#v %T; ", x, x); var y  ConcreteTypePtrReceiver = x.(ConcreteTypePtrReceiver);     fmt.Printf("%#v %T\n", y, y) } // compile error: 8: cannot use ConcreteTypePtrReceiver literal (type ConcreteTypePtrReceiver) as type InterfaceType in assignment: ConcreteTypePtrReceiver does not implement InterfaceType (someMethod method has pointer receiver)																								      //                131: impossible type assertion: ConcreteTypePtrReceiver does not implement InterfaceType (someMethod method has pointer receiver)
	
//	{ var x interface{} =    ConcreteTypePtrReceiver{1};   fmt.Printf("H1: %#v %T; ", x, x); var y *ConcreteTypePtrReceiver = x.(*ConcreteTypePtrReceiver);    fmt.Printf("%#v %T\n", y, y) } // H1: {1} main.ConcreteTypePtrReceiver{n:1} main.ConcreteTypePtrReceiver; panic: interface conversion: interface {} is main.ConcreteTypePtrReceiver, not *main.ConcreteTypePtrReceiver
//	{ var x InterfaceType =  ConcreteTypePtrReceiver{1};   fmt.Printf("H2: %#v %T; ", x, x); var y *ConcreteTypePtrReceiver = x.(*ConcreteTypePtrReceiver);    fmt.Printf("%#v %T\n", y, y) } // compile error: 8: cannot use ConcreteTypePtrReceiver literal (type ConcreteTypePtrReceiver) as type InterfaceType in assignment: ConcreteTypePtrReceiver does not implement InterfaceType (someMethod method has pointer receiver)

//	{ var x interface{} =    ConcreteTypePtrReceiver{1};   fmt.Printf("I1: %#v %T; ", x, x); var y  InterfaceType = x.(InterfaceType);                         fmt.Printf("%#v %T\n", y, y) } // I1: {1} main.ConcreteTypePtrReceiver{n:1} main.ConcreteTypePtrReceiver; panic: interface conversion: main.ConcreteTypePtrReceiver is not main.InterfaceType: missing method someMethod
//	{ var x InterfaceType =  ConcreteTypePtrReceiver{1};   fmt.Printf("I2: %#v %T; ", x, x); var y  InterfaceType = x.(InterfaceType);                         fmt.Printf("%#v %T\n", y, y) } // compile error: 8: cannot use ConcreteTypePtrReceiver literal (type ConcreteTypePtrReceiver) as type InterfaceType in assignment: ConcreteTypePtrReceiver does not implement InterfaceType (someMethod method has pointer receiver) 

	fmt.Println()
	fmt.Printf("--== Concrete Type with Pointer Method Receiver; Interface Dynamic Value is Pointer ==--\n")
//	{ var x interface{} =   &ConcreteTypePtrReceiver{1};   fmt.Printf("J1: %#v %T; ", x, x); var y  ConcreteTypePtrReceiver = x.(ConcreteTypePtrReceiver);     fmt.Printf("%#v %T\n", y, y) } // J1: &{1} &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver; panic: interface conversion: interface {} is *main.ConcreteTypePtrReceiver, not main.ConcreteTypePtrReceiver
//	{ var x InterfaceType = &ConcreteTypePtrReceiver{1};   fmt.Printf("J2: %#v %T; ", x, x); var y  ConcreteTypePtrReceiver = x.(ConcreteTypePtrReceiver);     fmt.Printf("%#v %T\n", y, y) } // compile error: 131: impossible type assertion: ConcreteTypePtrReceiver does not implement InterfaceType (someMethod method has pointer receiver)

	{ var x interface{} =   &ConcreteTypePtrReceiver{1};   fmt.Printf("K1: %#v %T; ", x, x); var y *ConcreteTypePtrReceiver = x.(*ConcreteTypePtrReceiver);    fmt.Printf("%#v %T\n", y, y) } // K1: &{1} &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver; &{1} &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver
	{ var x InterfaceType = &ConcreteTypePtrReceiver{1};   fmt.Printf("K2: %#v %T; ", x, x); var y *ConcreteTypePtrReceiver = x.(*ConcreteTypePtrReceiver);    fmt.Printf("%#v %T\n", y, y) } // K2: &{1} &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver; &{1} &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver

	{ var x interface{} =   &ConcreteTypePtrReceiver{1};   fmt.Printf("L1: %#v %T; ", x, x); var y  InterfaceType = x.(InterfaceType);                         fmt.Printf("%#v %T\n", y, y) } // L1: &{1} &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver; &{1} &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver
	{ var x InterfaceType = &ConcreteTypePtrReceiver{1};   fmt.Printf("L2: %#v %T; ", x, x); var y  InterfaceType = x.(InterfaceType);                         fmt.Printf("%#v %T\n", y, y) } // L2: &{1} &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver; &{1} &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver
}

output.txt

--== Concrete Type with Type Method Receiver; Interface Dynamic Value is Value ==--
A1: main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver; main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver
A2: main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver; main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver
C1: main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver; main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver
C2: main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver; main.ConcreteTypeTypeReceiver{n:1} main.ConcreteTypeTypeReceiver

--== Concrete Type with Type Method Receiver; Interface Dynamic Value is Pointer ==--
E1: &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver; &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver
E2: &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver; &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver
F1: &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver; &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver
F2: &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver; &main.ConcreteTypeTypeReceiver{n:1} *main.ConcreteTypeTypeReceiver

--== Concrete Type with Pointer Method Receiver; Interface Dynamic Value is Value ==--
G1: main.ConcreteTypePtrReceiver{n:1} main.ConcreteTypePtrReceiver; main.ConcreteTypePtrReceiver{n:1} main.ConcreteTypePtrReceiver

--== Concrete Type with Pointer Method Receiver; Interface Dynamic Value is Pointer ==--
K1: &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver; &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver
K2: &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver; &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver
L1: &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver; &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver
L2: &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver; &main.ConcreteTypePtrReceiver{n:1} *main.ConcreteTypePtrReceiver