# Abstract interface:
interface InterA
{
	routine size()=>int
	routine serialize()=>string
}

# Concrete interface for int:
interface InterA for int
{
	routine size(){
		io.writeln( "InterA<int>::size()", std.about(self) )
		io.writeln( "InterA<int>::size()", self.serialize() );
		return (int)self + 1;
	}
	routine serialize() => string { return "abc" + (string) self; }
}

@[test()]
var a: InterA = 123       # a: value type InterA<int>; variable type InterA;
io.writeln( std.about(a) )

class K
{
	routine size(){ return 1 }
	routine serialize() => string { return "abc"; }
}

a = K()
@[test()]
@[test()]
{{InterA<int>}}
@[test()]



@[test()]
var b = (InterA) 123;
io.writeln( std.about(b) )
@[test()]
@[test()]
{{InterA<int>}}
@[test()]




@[test()]
var c: InterA<int> = 123
io.writeln( std.about(c) )
@[test()]
@[test()]
{{InterA<int>}}
@[test()]




@[test()]
var c: InterA<int> = 123
var d: int = c
@[test()]
@[test()]
@[test()]



@[test()]
var e: list<InterA<int>> = { 123 }
e.append(456)
io.writeln( e )
@[test()]
@[test()]
{{abc123, abc456}}
@[test()]




@[test()]
var f: list<InterA> = { 678 }
f.append(456)
io.writeln( f );
@[test()]
@[test()]
{{abc678, abc456}}
@[test()]





interface InterB : InterA
{
    routine []( index: int ) => int 
}
interface InterB for int : InterA<int>
{
    routine []( index: int ) => int {
        return ((int)self & (1<<index)) >> index;
    }   
}


@[test()]
var k = (InterB) 0x7ffeff;
var f: list<InterA> = { 678 }
f.append( k ) 

io.writeln( f, k[1] )
@[test()]
@[test()]
{ abc678, abc8388351 } 1
@[test()]




@[test()]
var k = (InterB) 0x7ffeff;
var h = (InterA) k;
io.writeln( std.about(h) )
@[test()]
@[test()]
{{InterB<int>}}
@[test()]




@[test()]
var k = (InterB) 0x7ffeff;
var m: InterA = k;
io.writeln( std.about(m) )
@[test()]
@[test()]
{{InterB<int>}}
@[test()]




@[test()]
var k = (InterB) 0x7ffeff;
var s = (InterA<int>) k;
io.writeln( std.about(s) )
@[test()]
@[test()]
{{InterB<int>}}
@[test()]





@[test()]
interface InterC : InterB<int>
{
}
@[test()]
@[test()]
{{Invalid parent interface}}
@[test()]





@[test()]
interface InterC for int : InterB
{
}
@[test()]
@[test()]
{{Need symbol of interface}}
@[test()]





@[test()]
interface InterC {}
interface InterC for int : InterB
{
}
@[test()]
@[test()]
{{Invalid parent interface}}
@[test()]





@[test()]
interface InterC : InterA
{
}
interface InterC for int : InterB<int>
{
}
@[test()]
@[test()]
{{Invalid parent interface}}
@[test()]





@[test()]
interface InterC : InterA
{
	routine method();
}
interface InterC for int : InterA<int>
{
}
@[test()]
@[test()]
{{Incomplete concrete interface implementation}}
@[test()]