how to write a loop in Windbg like this

r @$t0=0;

$$ Loop to get all foo's
.foreach (CurrentFoo {!dumpheap -type George.George2.Foo -short}){
    $$ Increment # of Foo's
    r @$t0 = @$t0+1

    .printf "Length:t%dn", poi(${CurrentFoo}+0xc);
}
.printf "Number of Foo's: %dnnnnnnnnn", @$t0;