a's type didn't change. The trap was that the wrapping function returned its nested function instead of itself. You can do the same thing in other languages, it's just easier to slip into code in Copper. Let me illustrate with pseudo C code:
[code]
class F {
int mydata;
F( int a ) : mydata(a) {}
F* operator( int p ) { a=p; return new Function(0); }
};
myF = new F(10);
doSomething( &myFunc );
doSomething( myFunc() );
[/code]
This is a basic formula for how things appear "under the hood" in the VM. Notice that doSomething() accepts F*, but in the first case, the F instance passed has a different mydata value. In Copper, the above code corresponds to:
[code]
doSomething( myF )
doSomething( myF: ) or doSomething( myF() )
[/code]
